Let , neN, where N = {1, 2, 3, ..} is the set of positive integers. Define a function f: N N by f(x) = x modn [ f(x) = x modn means that f(x) is the remainder when x is divided by n. For example, f(7) = 7 mod5 = 2 since when dividing 7 by 5, the remainder is 2. f(14) = 14 mod5 = 4 since when dividing 14 by 5, the remainder is 4. ] Let n be your dd of birth. a) Compute f(31), and f(40) b) Compute the image f(N)