Homework #4

In the absence of a greenhouse effect, what would happen to Earth's oceans? a. They would evaporate b. They would freeze over c. They would be rapidly absorbed into surface rocks d. They would dissociate into ozone and hydrogen

b. They would freeze over

If photosynthesis were to disappear on Earth, a. the atmosphere would become less dense. b. oxygen would disappear from the atmosphere. c. the atmosphere would become hotter. d. nitrogen would disappear from the atmosphere. e. the amount of water vapor in the atmosphere would decrease.

b. oxygen would disappear from the atmosphere.

The presence of gases such as carbon dioxide and water vapor in a planet's atmosphere is direct evidence of _________ in a planet's history. a. high surface temperatures b. volcanic activity c. cometary impacts d. a lack of asteroid impacts e. the greenhouse effect

b. volcanic activity

Approximately how long after the Solar System formed did it take for oxygen to get to within 80 percent of its present abundance in Earth's atmosphere? a. 4 billion years b. 1 billion years c. 400 million years d. 1 million years e. Oxygen was always a component of Earth's atmosphere

a. 4 billion years

Which of the following statements is FALSE? a. The surface of Venus has very few craters primarily because asteroids burn up in its thick atmosphere. b. Geological features and the chemical composition of some rocks on Mars suggest liquid water flowed on the surface in the past. c. Darker regions of the Moon's surface have fewer craters and are approximately 1 billion years younger than the lighter regions. d. Volcanoes on Mars are larger, on average, than Earth's volcanoes because Mars does not have moving continental plates. e. Impact craters on Earth are erased over time because of erosion due to water and the recycling of its crust.

a. The surface of Venus has very few craters primarily because asteroids burn up in its thick atmosphere.

Which of the following processes did NOT contribute gas to Earth's secondary atmosphere? a. volcanism b. accretion c. oxidation d. comet impacts e. all of the above contributed gasses to Earth's secondary atmosphere

c. oxidation

The figure shows the continental plates of Earth and the locations of volcanoes and earthquakes. Which statement is FALSE? a. Earth's crust is broken up into 13 separate continental plates. b. Volcanoes occur more often where two plates are coming together rather than spreading apart. c. Earthquakes happen where two plates come together and when they spread apart. d. The Atlantic Ocean is getting smaller with time e. Southern California in the United States and Baja in Mexico are sliding northeastward relative to the rest of the North American Plate.

d. The Atlantic Ocean is getting smaller with time

If it were not for the greenhouse effect on Earth, a. there would be no liquid water on Earth. b. life as we know it would not have developed on Earth. c. it would be a much colder planet. d. there would be no oxygen in Earth's atmosphere. e. All of the above are results of the greenhouse effect.

e. All of the above are results of the greenhouse effect.

What is the reason Mercury has so little gas in its atmosphere? a. Its mass is small. b. It has a high temperature. c. It is close to the Sun. d. Its escape velocity is low. e. All of the above.

e. All of the above.

True or false? Homosapiens have existed for about 150,000 years. This is 0.09% of the time of the dinosaurs. This means that 1,480,000 years from now we will have lives 1% as long as the dinosaurs.

true