parent(jill, john). parent(john, pam). parent(pam, bob). parent(tom, bob). parent(tom, liz). parent(bob, ann). parent(bob, pat). parent(pat, jim). female(jill). female(pam). male(tom). male(bob). female(liz). female(ann). female(pat). male(jim). male(john). The above is the database for the prolog programs.  For program 1, write the predicates for 1) mother(X,Y) and 2) offspring(Y,X)  Here the first is interpreted as X is a mother of Y, and the second is Y is an offspring 0f X. For program 2, write the predicates for 1) sister(X, Y) and 2) ancestor(X,Y)  Here the first one is interpreted as X is a sister Y and the second one as X is an ancestor of Y. In the sister predicate you should include the following predicate different(X,Y) := not(X,Y) This will insure that a person cannot be her own sister. Of course, this predicate must also be included in the program before its used in "sister".