Determine whether or not the following pairs of predicates are unifiable. If they are, give the mostgeneral unifier and show the result of applying the substitution to each predicate. If they are not unifiable, indicate why. Assume that x, y, and z are variables, while other symbols are either predicates, constants, or functions.

a) P(B,A,B), P(x,y,z)

b) P(x,x), Q(A,A)

c) Older(Father(y),y), Older(Father(x),John).

d) Q(G(y,z),G(z,y)), Q(G(x,x),G(A,B)

e) P(f(x), x, g(x)), P(f(y), A, z)