Prove the identity of each of the following Boolean equations, using algebraic manipulation:

a) AB + B C' D' + A' B C + C' D = B + C' D

B) WY + W' Y Z' + WXZ + W' X Y' = WY + W' X Z' + X' Y Z' + X Y' Z

c) A C' + A' B + B' C + D' = (A' + B' + C' + D')(A + B + C + D')

The ' is the complement of the variable preceding it. Please help if anyone can.

Thanks so much!!!!!