c & e only please

2.1 + Demonstrate the validity of the following identities by means of truth tables: (a) De Morgan's theorem for three variables: (x + y + z)' = x'y'z' and (xyz)' = x y + z' (b) The distributive law: x + yz = (x + y)(x + z) (c) The distributive law: x(y + z) = xy + xz (e) Associative law: x(yz) = (xy)z