13. Implement the following Boolean function with a 4 x 1 multiplexer and external gates. (a) Fi(A, B, C, D)=E(1, 3, 4, 11, 12, 13, 14, 15) (6) F (A, B, C, D) = (1, 2, 5, 7, 8, 10, 11, 13, 15) Connect inputs A and B to the selection lines. The input requirements for the four data lines will be a function of variables cand D. These values are obtained by expressing Fas a function of cand D for each of the four cases when AB = 00, 01, 10, and 11. These functions may have to be implemented with external gates