. Answer the following:

a. What is {1, 2, 3} {1, 4, 16}?

b. What is {1, 4, 16} {1, 2, 3}?

c. What is {1} {1} {1}?

d. What is {1, 2} {2, 3} {1, 4, 16}?

e. Suppose A B = {1, 1, 2,1}. What are A and B?

Which of the following functions f : {0, 1, 2, 3} {0, 1, 2, 3} are onto?

a. f(x) = x

b. f(x) = x2 mod 4

c. f(x) = x2 x mod 4

d. f(0) = 3, f(1) = 2, f(2) = 1, f(3) = 0

e. f(0) = 1, f(1) = 2, f(2) = 1, f(3) = 2