APCSP Data Representation 2

Question 1

Which of the following best describes why computers use binary (base-2) rather than decimal (base-10) to store data?

Accepted Answer

Electronic circuits naturally represent two states (on/off), making binary practical

Answer

Electronic components like transistors naturally exist in two stable states (on/off or high/low voltage), making binary the most practical number system for hardware.

Question 2

How many unique values can be represented using 4 bits?

Accepted Answer

16

Answer

With n bits you can represent 2^n unique values; 2^4 = 16.

Question 3

The hexadecimal value 0xFF is equivalent to which decimal value?

Accepted Answer

255

Answer

F in hex equals 15, so 0xFF = 15×16 + 15 = 240 + 15 = 255.

Question 4

A color image is stored using 24-bit color (8 bits per channel for red, green, blue). How many distinct colors can it represent?

Accepted Answer

16,777,216

Answer

24 bits total gives 2^24 = 16,777,216 distinct color combinations.

Question 5

Which encoding standard assigns a unique number to every character and supports over 140,000 characters from multiple languages and symbol sets?

Accepted Answer

UTF-8 / Unicode

Answer

Unicode (with UTF-8 as a common encoding) assigns code points to over 140,000 characters covering most of the world's writing systems.

(APCSP) AP Computer Science Principles Practice Test

(APCSP) AP Computer Science Principles Practice Test

APCSP Data Representation 2