Problem 3. In each case construct, if possible, a binary (n, M, d)-code. If no such code exists, explain why.

(a) (n, M, d) = (7, 2, 7),

(b) (n, M, d) = (5, 3, 4),

(c) (n, M, d) = (5, 4, 3).

(d) (n, M, d) = (6, 4, 4),

(e) $(n, M, d) = (4, 8, 2),

(f) $(n, M, d) = (8, 29, 3).