please help

Express the range of each function using roster notation.

(a)

Let A = {2, 3, 4, 5}. f: A Z such that f(x) = 2x - 1.

(b)

Let A = {2, 3, 4, 5}. f: A Z such that f(x) = x².

(c)

f: {0,1}⁵ Z. For x {0,1}⁵, f(x) is the number of times "01" occurs in the string. For example f(01101) = 2 because the string "01" occurs twice in "01101". The first occurrence starts at the first bit. The second occurrence starts in at the fourth bit.

(d)

f: {0,1}⁵ Z. For x {0,1}⁵, f(x) is the number of 1's that occur in x. For example f(01101) = 3, because there are three 1's in the string "01101".