2. (20 points) Given a, b,c, d, n are integers with n > 1, assume a = c (mod n) and b = d (mod n) Prove each of the following statements.
(a) a2 = b2 (mod n)
(b) am = bm (mod n) for every integer m 1 using induction on m.
(c) (a+c) =(b+d) (mod n)
(d) (a2 + c) = (b2+ d) (mod n)