For each of the following propositions construct a truth table and indicate whether it is a tautology (it is always true), a contradiction (it is never true), or a contingency (its truth depends on the truth of the variables). There should be a column for each operator. There should also be three columns for an 7. a) PVP b) PA P c) (PVQ) 1 (PV-Q)^GP VQ)^GP V-Q) d) (P1(Q V R)) = ((P1Q) V (PAR)) e) ((P = Q) v ( RS)) = ((PVR) = (Q v S)) f) 7(P1Q) A (PV-Q) g) -( PQ) = GPA-Q)