Marked_activaten__conssMarked_cons2ndfromMarked_2ndconsn__fromMarked_fromactivateX2X1ZYX2nd(cons(X,n__cons(Y,Z)))activate(Y)from(X)cons(X,n__from(s(X)))cons(X1,X2)n__cons(X1,X2)from(X)n__from(X)activate(n__cons(X1,X2))cons(X1,X2)activate(n__from(X))from(X)activate(X)X2nd(cons(X,n__cons(Y,Z)))activate(Y)from(X)cons(X,n__from(s(X)))cons(X1,X2)n__cons(X1,X2)from(X)n__from(X)activate(n__cons(X1,X2))cons(X1,X2)activate(n__from(X))from(X)activate(X)XMarked_2nd(cons(X,n__cons(Y,Z)))Marked_activate(Y)Marked_from(X)Marked_cons(X,n__from(s(X)))Marked_activate(n__cons(X1,X2))Marked_cons(X1,X2)Marked_activate(n__from(X))Marked_from(X)