a) Consider the full adder function: sum(C-1, X, y) = (c, s) Where xi, y, are the im bits of the binary numbers X and Y, C-, is the carry in and the outputs are: C, the carry out and s is the sum output. Write the equations of both c, and s, in conjunctive normal form (CNF), i.e. in standard product of sums (SPOS). b) As a result of a) above, design the corresponding circuit for the full adder, using only the NOR gates