2. The notation {f(x): x S} means "the set of all values that can be produced by substituting an element x of set S into f(x)." For example, the set of all odd integers can be expressed as {2k+1kZ}. Let A and B be sets defined as follows: A = {12m 17: m E Z} B = {4n+7:n Z} (a) (1 point) List any three elements of A. (b) (1 point) List any three elements of B. (c) (3 points) Prove that AC B. Use the definition of subset: ACB if every element of A is also an element of B.