Final answer:
The number of possibilities for a.) the number of arrangements of four different colored blocks is 24, and b.) the number of ways four people can be arranged in a line is also 24.
Step-by-step explanation:
For part a) of the question, if there are four different colored blocks, the number of arrangements can be found by using factorial. The number of possibilities is 4! (four-factorial), which equals 4 · 3 · 2 · 1 = 24.
For part b) of the question, if there are four people to be arranged in a line, the number of arrangements can also be found by using factorial. The number of possibilities is 4! = 4 · 3 · 2 · 1 = 24.