8,9,10
100. The Greenhouse effect produces excess heat in a planet's atmosphere by A. trapping infrared radiation from escaping into space. B. clouds blocking the surface from receiving any infrared radiation. C. trapping light gases from escaping into space. D. trapping ultraviolet light in the upper atmosphere of the planet
a
103. Which of the terrestrial planets has the most difficult time retaining an atmosphere? A. Mercury B. Venus C. Earth D. Mars
a
14. ____ pushes gas and dust particles out of the solar nebula by the light from the sun A. radiation pressure B. outgassing C. condensation D. accretion E. differentiation
a
17. Which one of the following IS a characteristic of Jovian planets? a) low average density b) orbits inside the asteroids c). craters in old surfaces d) small diameters e) very few satellites
a
18. Which one of the following IS NOT a characteristic of terrestrial planets? A. low average density B. orbits inside the asteroids C. craters in old surfaces D. small diameters E. very few satellites
a
22. Once a terrestrial planet had formed from a large number of planetesimals, heat could have melted it and allowed it to differentiate into metallic core of ____density and a rocky mantle or crust of ______ density. A. higher; lower B. lower; higher C. Wrong! The interior stays solid D. Wrong! There is no separation according to density.
a
27. The planets all lie in nearly the same plane resulting in a disk-like structure for the solar system. This disk-like structure is believed to exist because A. the solar nebula from which the planets formed had a disk-like structure. B. the bipolar flow from the young sun cleared all material out of the nebula except that in the disk. C. Jupiter's gravity was great enough to pull all of the other planets to the plane of its orbit. D. the Milky Way Galaxy from which the planets condensed has a disk like structure
a
28. Which one of the following objects is most like the planetesimals that formed in the solar nebula? A. asteroids B. Earth C. Saturn D. Venus E. the sun
a
30. Accretion among the grains in the solar nebula would have been aided by A. static electricity. B. gravity. C. high-velocity collisions. D. all of the above E. none of the above
a
31. Based on current observations, ____ has a heavy element core, and a very compressed liquid layer and atmosphere both made mostly of hydrogen. A. Jupiter B. Pluto C. Venus D. an asteroid E. a meteor
a
45. How is radioactive dating used to determine the age of an object? A. Both the amounts of radioactive and decay material are measured. Using these with the radioactive material's half- life, the age can be estimated. B. The amount of radioactive material is measured. Using this with the radioactive material's half-life, the age can be estimated. C. The amount of decay material is measured. Using this with the radioactive material's half-life, the age can be estimated. D. The amount of heat generated by radioactive dating is measured to determine age.
a
51. Earth's magnetic field is generated by the dynamo effect in the A. molten metallic core. B. solid central core. C. plastic mantle. D. the crust. E. aurora.
a
55. The greenhouse effect occurs on Earth because carbon dioxide is A. transparent to visible light and opaque to infrared radiation. B. opaque to visible light and transparent to infrared radiation C. totally opaque to both visible light and infrared radiation D. totally opaque to both visible light and infrared radiation
a
6. The satellites discovered by galileo A. orbit the planet Jupiter B. orbit the terrestrial planets C. orbit asteroids D. orbit mars E. orbit extrasolar planets
a
61. In the development of a terrestrial planet, the stage of ____ when dense material settled to the core and less dense to the outer parts. A. differentiation B. cratering C. glaciation D. accretion E. flooding
a
66. The lunar maria are A. the lava plains of the lunar lowlands. B. the smooth plateaus of the lunar highlands. C. less than one billion years old. D. moving plates of lunar crust. E. older than the lunar highlands.
a
72. In the fission theory of the Moon's origin A. the Moon broke from a rapidly spinning Earth B. the Earth and its Moon formed from the same cloud of matter C. the Moon formed elsewhere in the solar nebula and was later captured by Earth. D. the Moon formed when a very massive planetesimal smashed into the young Earth.
a
75. Which hypothesis concerning the formation of the Moon makes predictions that best fit the observed lunar data? A. The large impact hypothesis B. The fission hypothesis C. The capture hypothesis D. The condensation hypothesis E. The regolith hypothesis
a
79. The geology of Venus appears to be dominated by A. volcanism. B. plate tectonics. C. erosion by flowing water. D. impact cratering. E. strip mining.
a
9. After the first solid grains formed in our solar system, these particles could then grow by the process of ____, the collision and sticking of one particle with another to continue the formation of planetesimals. Each of these has many atoms or molecules. A. accretion B. sublimation C. hydration D. condensation E. vaporization
a
92.____ is a very long and deep canyon on Mars. A. Valles Marineris B. Ishtar Terra C. Tharsis Bulge D. Lobate Scarp E. Phobos
a
99. The moon's distance from Earth is measured very accurately by bouncing a laser beam off of a small mirror left on the surface of the moon. If a laser is fired at the moon and the signal returns in 2.6 seconds, what is the distance to the moon? A. 390,000 km B. 390,000 m C. 780,000 km D. 780,000 m
a
105. What do astronomers generally believe about the origin of Mars' moons? A. They formed with the planet out of the protoplanetary material. B. They formed elsewhere and were captured at a later time. C. They were ejected from Mars during its formation. D. They were once a single moon and a later catastrophic event broke them in two.
b
11. ___ is the separation of material in a newly formed planet or asteroid according to density. this happens when the object becomes molten A. accretion B. differentiation C. condensation D. outgassing E. sublimation
b
15. Accretion is A. the adding of material to an object an atom or molecule at a time B. the adding of material to an object by collection or solid particles C. the release of gas from rocks as they are heated D. the largest of the galilean satellites E. caused by the bombardment of the solar wind
b
20. A(n) ____ is a solar system object that enters Earth's atmosphere and becomes very hot due to friction between the object and Earth's atmosphere and does not survive to reach the surface. A. asteroid B. meteor C. comet D. meteoroid E. planetesimal
b
23. The condensation sequence suggests that ____ should condense as solids closest to the sun. A. hydrogen and helium B. metals and metal oxides C. silicates D. ices of water, methane, and ammonia
b
29. The large planetesimals would have grown faster than the smaller planetesimals because A. they were moving faster in their orbits than the smaller planetesimals. B. their stronger gravity would pull in more material. C. there was more material located near them that could be accreted. D. the smaller planetesimals were covered by a layer of material that was lost during collisions. E. all of the above
b
35. The uncompressed density of a planet in our solar system A. is greatest for the Jovian planets. B. is greatest for the planets closest to the sun. C. is greatest for the planets furthest from the sun. D. is greatest for the planets with the largest mass. E. is greatest of the planet with the largest radius
b
37. On a photograph of the Earth's moon, the moon measures 30 cm in diameter and a small crater measures 0.2 cm. The moon's physical diameter is 1738 km. What is the physical diameter of the small crater? A. about 1738 km B. about 12 km C. about 520 km D. about 350 km E. about 3.5 km
b
44. The asteroid belt is found between which two planets' orbits? A. Earth and Mars B. Mars and Jupiter C. Jupiter and Saturn D. Venus and Earth
b
48. That Earth ____ , evidence that Earth differentiated. A. rotates slowly B. has an average density that is higher than the density of the crust C. has no magnetic field D. has a surface that is 75% water E. all of these
b
49. In contrast to the outer solid mantle, parts of the central regions of Earth's interior are thought to be fluid because A. P seismic waves cannot make it through those regions B. S seismic waves cannot make it through those regions C. both P and S seismic waves cannot make it through those regions D. both P and S seismic waves easily make it through those regions
b
50. The central regions of Earth's core are solid because A. the composition at the center of the core is lower in iron. B. the pressure at the center raises the melting point. C. the magnetic field cannot penetrate into the center of the core. D. convection does not extend all the way to the center of the core. E. Earth initially formed from solid particles in the solar nebula.
b
59. The ozone layer is A. transparent to ultraviolet radiation. B. opaque to ultraviolet radiation. C. opaque to visible light. D. opaque to infrared radiation. E. responsible for producing most of the oxygen that animal life needs.
b
63. Motion of the plates of Earth's crust is thought to be due to A. the solar wind. B. convection from the hot interior. C. tides in the oceans. D. friction between wind and the land surface. E. Earth's magnetic field.
b
65. Slow surface evolution on the moon is limited to A. low density masses of rock rising from the interior. B. low level meteorite impacts. C. moonquakes disturbing the surface features. D. motion along a network of small faults. E. all of the above
b
71. In the condensation theory of the Moon's origin A. the Moon broke from a rapidly spinning Earth B. the Earth and its Moon formed from the same cloud of matter C. the Moon formed elsewhere in the solar nebula and was later captured by Earth. D. the Moon formed when a very massive planetesimal smashed into the young Earth.
b
74. That Mercury has a large iron core is evidenced by A. the large lobate scarps. B. the large mean density of Mercury. C. the lava flows near Caloris Basin. D. all of the above E. none of the above
b
81. The greenhouse effect keeps Venus hot because A. the atmosphere contains free oxygen. B. the atmosphere is predominantly carbon dioxide. C. the surface converts infrared into visible radiation. D. the surface is free of sulfur compounds. E. the magnetic field traps a large number of particles from the solar wind.
b
83. The flow patterns found on the surface of Mars and the number of craters on top of them suggest that A. Mars is today a liquid water-rich world. B. the climate on Mars was different billiond of years ago. C. volcanism is occurring on Mars. D. the polar caps are made of liquid water. E. all of the above
b
85. Coronae on Venus are believed to be A. impact craters. B. caused by rising convection currents in the interior of Venus. C. the result of plate tectonics. D. located only in the polar regions of Venus. E. much older than the highlands such as Ishtar Terra.
b
94. Which of the planets or satellite plotted in the diagram in the previous question is least able to hold an atmosphere? A. Mars B. Moon C. Mercury D. Venus E. Earth
b
97. Most terrestrial planets have portions of their surface that appear to be significantly older than other portions of their surface. What evidence suggests that the surface of Venus is all of the same age? A. Photos taken by probes that landed on Venus showed that all of the rocks were of the same age. B. The craters on Venus are randomly distributed in size and number across the surface. C. The volcanoes on Venus are not found in isolated groups, but are scattered around the planet. D. a and b E. all of the above
b
12. A newly formed planet or large asteroid becomes molten due to A. the last infalling objects B. decay of radioactive element isotopes C. both of the above D. none of the above. newly formed planets remain solid inside
c
16. Outgassing is A. the adding of material to an object an atom or molecule at a time B. the adding of material to an object by collection of solid particles C. the release of gas from rocks as they are heated D. the largest of the galilean satellites E. caused by the bombardment of the solar wind
c
19. A future news release might report that a new planet has been found around a star very similar to our sun. This newly discovered planet is claimed to have a mass 40 times that of Earth and is located nearly 25 AU from the star it orbits. Which of the following would be a reasonable prediction about this planet? I. The planet will probably have a mean density of around 5 g/cm3. II. The planet will probably have a radius of around five to ten times greater than Earth's. III. The planet will probably have several satellites. IV. The planet will probably have a composition that is mostly hydrogen and helium. A. I & IV B. I, II, & III C. II, III, & IV D. I, II, & IV E. I, II, III, & IV
c
25. Protoplanets of the Jovian planets could have grown very hot from A. heat for the sun. B. radioactivity of light elements such as hydrogen and helium. C. the in fall of material at high velocity. D. tidal forces due to the sun. E. collisions with large planetesimals.
c
26. The terrestrial planets are thought to have formed by accreting solid plantesimals all with about the same composition. This means A. they were initially molten forming an iron core first, then they accreted a silicate crust later. B. they were initially molten forming a silicate core first, then they accreted an iron crust later. C. they were initially collections of solid particles which melted then differentiated into a high density iron metal core and low density silicate crust. D. they were initially collections of solid particles which melted then differentiated into a high density silicate core and low density iron metal crust.
c
38. The speed of the solar wind is approximately 400 km/s and the distance from the sun to Saturn is 9.5 AU (1AU = 1.5×10^8 km). How long does it take a particle in the solar wind to reach Saturn? A. about 4.1 hours B. about 4.1 days C. about 41 days D. about 4.1 years E. about 41 years
c
4. An extrasolar planet is A. a planet that orbiters our sun that we have not yet discovered B. one not needed for the formation of our solar system which is kept in a special area just in case C. a planet found orbiting around a star other than the sun D. another name for an asteroid E. a planet extra close to our sun
c
40. The diagram below illustrates the radioactive decay of Potassium (40K), which has a half-life of 1.3 billion years. If a lunar rock is found that currently contains 5 grams of 40K, and it is determined that the sample contained 20 grams when it was formed, how old is the lunar rock? A. 6.5 billion years B. 19.5 billion years C. 2.6 billion years D. 3.9 billion years E. 4.6 billion years
c
41. The solar nebula theory is NOT able to explain which of the following observed characteristics of the solar system? Another theory would be needed. A. Common direction of rotation of the planets. B. Common direction of revolution of the planets. C. The formation of hydrogen atoms in the solar system from subatomic particles. D. The density of the Jovian planets.
c
43. Compared to the terrestrial planets, Jovian planets A. have a higher density. B. have a smaller number of moons. C. have a much larger diameter. D. are much hotter.
c
56. Which of these gases is most responsible for the greenhouse effect on Earth? A. oxygen (O2) B. nitrogen (N2) C. carbon dioxide (CO2) D. ozone (O3) E. ammonia (NH3)
c
58. The Himalayan Mountains are rugged, jagged peaks and the Appalachians are smooth and rolling. Why is there a difference? A. The Himalayas are much older and the rocks have begun breaking off. B. The Himalayas are volcanic mountains and the Appalachians are not. C. The Appalachians are much older and have been smoothed by erosion. D. The Appalachians are younger and just started to be thrust upward by plate tectonics. E. a and d
c
68. Compared to the Earth, the moon is no longer geologically active because A. it is rotating too slowly. B. its radioactive elements were never abundant. C. it is much smaller in mass. D. its crust is too thin. E. it does not have water on its surface.
c
82. Measurements of the magnetic field of Venus reveal that the A. planet has a large iron core. B. interior of the planet is molten. C. planet has no detectable magnetic field. D. planet rotates backwards. E. magnetic field is responsible for large auroral displays (northern lights) on Venus.
c
86. Which of the solar system objects listed below is most similar to Earth in terms of mass and density? A. Mercury B. Moon C. Venus D. Mars E. Deimos
c
87. The graph below plots the escape velocity of each planet along the vertical axis and its surface temperature along the horizontal. The lines plotted in the figure are the speeds of the fastest gas particles as a function of temperature for various gases. Which of the gases plotted in the diagram could be retained in the atmosphere of Mars? A. only CO2 B. only NH3 C. CO2, NH3, and O2 D. only H2 E. H2 and He
c
88. How rapidly a planet loses its atmosphere de pends on the planet's I. escape velocity (determined by mass and radius) II. atmospheric composition III. temperature IV. rotation period A. I & II B. III & IV C. I, II, & III D. II, III, & IV E. I, II, III, & IV
c
98. One hypothesis suggested to explain the uniform age of the surface of Venus is that A. Venus' surface is 4 billion years old and has not been affected by flooding or slow evolution. B. Venus' surface is made of rocks that are much harder than Earth's and thus last longer. C. Venus periodically goes through a catastrophic melting of the entire surface. D. Venus' clouds protect it from meteorites so that very few impacts occur to change its surface. E. dust storms deposit large amount of dust on the surface making it appear of uniform age
c
101. Mercury's major atmospheric gas is A. oxygen. B. hydrogen. C. carbon dioxide. D. Misleading; the atmosphere is virtually nonexistent.
d
102. Why does Mars have seasons similar to the Earth? A. Mars is roughly the same distance from the sun as Earth. B. Mars has the same size as the Earth. C. The shape of Mars' orbit is the same as the Earth's. D. Mars' rotational axis is tilted relative to its orbit like the Earth's.
d
104. What physical property of Venus is vastly dissimilar compared to Earth? A. Radius B. Mass C. Density D. Surface temperature
d
2. The hydrogen in our solar system was created from subatomic particles in A. the earth B. our sun C. Jupiter D. the big bang E. supernovas
d
21. The age of the solar system is believed to be approximately 4.6 billion years based on the data from A. samples of lunar rocks. B. samples of Earth rocks. C. samples of meteorites. D. all of the above E. none of the above
d
24. Condensation in the solar nebula probably led to the formation of A. icy grains beyond the present orbit of Jupiter. B. metallic grains near the present orbit of Mercury. C. silicate grains near the present orbit of Earth. D. all of the above E. none of the above
d
3. The oldest rocks found on earth are about ____ years old A. 14 billion B. 10.5 billion C. 7 billion D. 3.9 billion
d
32. If a star is found with five planets orbiting it, and a process like that described in the solar nebula theory formed the planets, which of the planets would be expected to have the greatest uncompressed density? A. The one farthest from the star. B. The one with the greatest mass. C. The one with the greatest radius. D. The one closest to the star. E. The one that has liquid water on its surface.
d
33. Part of the current atmosphere of Earth is believed to be A. the remnants of the original hydrogen and helium gas from the solar nebula attracted by the protoplanet. B. the result of the melting and vaporizing of the glaciers from the last ice age. C. composed primarily of hydrogen and helium. D. composed of gases that were out gassed from the heated rocks sometime after the planet formed. E. the result of a collision between the sun and another star.
d
42. What observation made of other stars seems to suggest the solar nebula hypothesis is correct? A. Stars are found to exist more often in binaries than by themselves. B. Protostars are seen to radiate much of their light at infrared wavelengths. C. Nearby stars tend to be low mass red dwarfs. D. Young stars are found to have hot disks that surround them.
d
46. How is the presence of space debris accounted for by solar system models? A. Space debris is left over material from the early solar system that never formed into a planet. B. Space debris was formed by the collision of objects after the planets formed. C. Space debris is material that existed in our region of space before the sun formed. D. Both a and b E. All of the above
d
47. Which of the following is NOT one of the four stages in the development of a terrestrial planet? A. flooding B. cratering C. slow surface evolution D. fusion of hydrogen to helium E. differentiation
d
54. The oxygen in Earth's atmosphere A. was manufactured inside stars. B. was added to the atmosphere by plant life. C. has grown more abundant since the origin of Earth. D. all of these E. none of these
d
64. Why would a decrease in the density of the ozone layer create a public health concern? A. The greenhouse effect would not be as efficient and the temperature of Earth would decrease. B. The greenhouse effect would be more efficient and the temperature of Earth would increase. C. Plant life would no longer have the ozone it needs for photosynthesis to create chlorophyll. D. Ultraviolet radiation from the sun would bombard Earth. E. none of the above
d
67. The presence of vesicular basalts among the lunar rock samples shows that A. the lunar surface was fragmented by meteorite impacts. B. volcanism did not occur on the moon. C. the crust must have been made of anorthosite. D. molten lava once flowed over the lunar surface. E. the moon was once hit by a very large meteorite.
d
7. The first small solid grains or flakes formed in our solar system by the process of _____, the addition of material to an object an atom or motorcycle at a time A. accretion B. sublimation C. hydration D. condensation E. vaporization
d
70. In the giant impact theory of the Moon's origin, A. the Moon broke from a rapidly spinning Earth B. the Earth and its Moon formed from the same cloud of matter C. the Moon formed elsewhere in the solar nebula and was later captured by Earth. D. the Moon formed when a very massive planetesimal smashed into the young Earth.
d
73. The theory that Mercury shrank slightly when it was young has been proposed to explain A. extended lava plains. B. large craters. C. magnetic field. D. lobate scarps. E. regolith.
d
76.____ are believed to have formed on Mercury when the planet's interior cooled and shrank. A. Jumbled terrain B. The highlands C. Maria D. Lobate scarps E. Sinuous rilles
d
77. That the moon has no magnetic field implies that A. the moon is spinning too slowly to produce a magnetic field. B. the interior of the moon is too hot to produce a magnetic field. C. the crust of the moon is so thick that the magnetic field can not get out of the interior. D. the moon's core contains little if any molten iron. E. the moon is moving further from Earth.
d
78. Which of the following are not found on Venus? A. arachnoids B. coronae C. rolling plains D. lobate scarps E. high atmospheric pressure
d
8. The first solid grains of ________ formed in hot regions near the sun. much farther from the sun the first grains (or rather flakes) of ______ also formed by a similar process as the close-in grains, ____. A. water ice: iron: accretion B. iron: water ice: accretion C. water ice: iron: condensation D. iron: water ice: condensation
d
80. The surface of Venus has been studied A. using radar maps made from Earth. B. using radar maps made from satellites orbiting Venus. C. using spacecraft that have landed on the surface of Venus. D. all of the above E. only b and c
d
84. Which of the following supports the idea that the Martian crust is not divided into moving plates like those on Earth? I. the size of Olympus Mons II. the lack of folded mountain chains III. the lack of rift valleys outlining entire plates IV. the presence of dry river beds and sea floors A. I & II B. II & III C. II, III & IV D. I, II, & III E. I, II, III, & IV
d
91. Mars has a sufficient mass and a low enough temperature that water molecules could exist in its atmosphere as vapor. One reason Mars' atmosphere does not contain a significant amount of water vapor is that A. Mars formed in a part of the solar nebula that lacked oxygen. A. Mars formed in a part of the solar nebula that lacked hydrogen. B. All of the water vapor was released in the impact that formed Deimos. C. Ultraviolet radiation breaks the water molecule into less massive particles that can escape. D. The water molecule combines readily with chlorine to form hydrochloric acid.
d
95. The extreme size of volcanoes on Mars indicates that A. Mars has a much thicker crust than Earth. B. water once flowed in streams on Mars. C. large moving plates have not formed on Mars. D. a and c E. a, b , and c
d
96. Besides Earth, which of the terrestrial planets and/or satellites of terrestrial planets show(s) evidence for the A. possible existence of liquid water flowing on its surface in the past? B. Venus C. The Moon D. Phobos E. Mars F. None of the terrestrial planets or satellites show such evidence.
d
1. The iron in our solar system was created from smaller mass atomic nuclei in A. the earth B. our sun C. Jupiter D. the big bang E. supernovas
e
10. Protoplanets A. grew in size primarily by accretion B. grew in size primarily by condensation C. are still visible today as the terrestrial planets D. grew in size by collecting the particles in the solar wind E. grew in size by the collision and coalescing of planetesimals
e
13. The jovian problem refers to A. the high speed with which the jovian planets rotate on their axes B. the large number of satellites that orbit each jovian planet C. the existence of rings around the jovian planets D. the excess heat radiated by the larger of the jovian planets E. the apparently short period of time that disks exist around stars from which jovian planets can form
e
34. The most important effect in clearing the solar nebula of gas and dust was A. impacts by planetesimals. B. the solar wind. C. the sun's magnetic field. D. the asteroid belt. E. radiation pressure.
e
36. Pegasi is important because A. it is a pulsar with planets orbiting around it. B. it is a star with a planet that is known to support intelligent life. C. it is the largest satellite of Jupiter. D. it is the largest known asteroid. E. it is the first star like our sun that was found to have a planet orbiting it.
e
39. Suppose that Mercury grew to its present size in 1 million years through the accretion of particles averaging 100 g each. On average how many particles did Mercury capture each second? Note: Mercury has a mass of 3.3×10^23 kg and a radius of 2439 km. A. about 24 particles per second B. about 3.3×10^21 particles per second C. about 67 particles per second D. about 100 million particles per second E. about 100 billion particles per second
e
5. _____ are located beyond the asteroid belt (3 au) from the sun, have extremely large masses and very low densities A. comets B. extrasolar planets C. asteroids D. terrestrial planets E. jovian planets
e
52. The youngest parts of Earth's crust are A. the bottom layer found in the walls of the Grand Canyon. B. the continents. C. the continental margins. D. the Appalachian Mountains. E. the midocean rifts.
e
53. Which of the following is not produced by plate tectonics? A. midocean rifts B. rift valleys C. the ring of fire D. the Appalachian Mountains E. Earth's magnetic field
e
57. Earth possesses few visible craters and the moon possesses many. This is because A. Earth formed later than the moon and, therefore hasn't encountered as many meteoroids. B. the moon doesn't have an atmosphere that could burn up many of the meteorites before impacting. C. erosion and plate tectonics have slowly removed evidence of past cratering on Earth. D. all of the above E. only b and c
e
60. In the development of a terrestrial planet, the stage of ____ occurred when molten rock flowed through fissures and filled deep basins. A. differentiation B. cratering C. glaciation D. accretion E. flooding
e
62. Slow surface evolution is caused by A. wind erosion. B. plate tectonics. C. differentiation. D. all of the above E. a and b
e
69. The presence of breccias among the lunar rock samples shows that A. volcanism did not occur on the moon. B. molten lava once flowed over the lunar surface. C. the crust must have been made of anorthosite. D. water once existed on the moon in the form of small lakes and streams. E. the lunar surface was fragmented by meteorite impacts.
e
89. The crust of Mars is believed to ____ than Earth's. A. be much thinner B. be younger C. contain more water D. be more geologically active E. be much stronger
e
90. The moons of Mars are believed to be A. composed primarily of iron and nickel. B. composed primarily of frozen gases of water and carbon dioxide. C. orbiting Mars in a direction opposite to the direction that Mars rotates. D. formed from material ejected from Olympus Mons and other large volcanoes on Mars. E. captured asteroids.
e
93. The graph below plots the escape velocity of each planet along the vertical axis and its surface temperature along the horizontal. The lines plotted in the figure are the average speeds of gas particles as a function of temperature for various gases. Which of the planets plotted in this diagram has the greatest escape velocity? A. Mars B. Moon C. Mercury D.Venus E. Earth
e
