(a) (4%) Show that the set ( AND, OR, NOT) of logic operations is functionally complete, that is, any Boolean function can be represented with this set of logic operations.

(a) (10%) Prove by induction that it represents an odd-parity function, that is, it evaluates to 1 if and only if the assignment to variables X1,...,Xn contains an odd number of 1's. (For example, the assignment (X1, X2, X3, X4)= (1,0,0,0) contains one 1.)