Comp Sci Code.org Questions

What is the most important quality of lossless compression? A. The data is transformed to usually make it smaller. It can always be re-constructed back to the original. B. The data is transformed to always make it smaller. It can always be re-constructed back to the original. C. The data is transformed to usually make it smaller. It cannot always be re-constructed back to the original. D. The data is transformed to always make it smaller. It cannot always be re-constructed back to the original.

A

Two schools are merging and to adapt to the increased size of the student body, the school is changing its system for keeping track of all student IDs from a system that uses 4-bit binary numbers to one that uses 8-bit binary numbers (AKA 1 byte). Which of the following best describes what effect this change will have? A. The 8-bit system will be able to represent twice as many values as the 4-bit system. B. The 8-bit system will be able to represent sixteen times as many values as the 4-bit system. C. The 8-bit system will be able to represent eight times as many values as the 4-bit system. D. The 8-bit system will be able to represent the same number of values as the 4-bit system, it will just include more zeros.

B

Which of the following would result in a better digital approximation of an analog black and white image? A. Increasing the size of each sample square, thus decreasing the number of samples taken. B. Decreasing the size of each sample square, thus increasing the number of samples taken. C. Using fewer bits to represent the image. D. Using decimal numbers to represent each pixel.

B

Which statement about analog and digital images is true? A. With advances in technology, digital images look exactly like the analog images they represent. B. Sampling an analog image more frequently produces a digital image with a better representation. C. Analog images come from data that is measured at regular intervals. D. Digital images come from data that is measured continuously.

B

What base is decimal?

Base 10

What base is binary?

Base 2 (0,1)

How is a Creative Commons license different from a regular copyright? A. It is different in name only - in practice, it does the same thing. B. It allows others to share and reuse your work if they pay you first. C. It allows your work to be shared, reused, and remixed to help spark more creativity. D. It is the most restrictive type of copyright, not allowing anyone to use your work for any reason.

C

Assume your friend just sent you 32 bits of pixel data (just the 0s and 1s for black and white pixels) that were encoded after sampling an image. Choose the two statements that are true. A. The 32 bits of pixel data is enough to produce the image using the widget. Nothing else is needed. B. The digital image would be an exact copy of the analog image. C. The correct width and height must be input into the pixelation widget to produce the image. D. The fact that only 32 bits were used to represent the image indicates relatively large sample squares were used. The digital image may vary from the analog image significantly.

C and D

"The binary pattern 01000001 represents the number 65." Write a brief response explaining whether you believe this statement is always true. Explain your reasoning.

Yes it is always true

When using bits to represent fractions of a number, can you create all possible fractions? Why or why not?

No because bits can create fractions like .5 and .25 but not fractions like .6.

Modern car odometers can record up to a million miles driven. What happens to the odometer reading when a car drives beyond its maximum reading?

The odometer rests to 0