How many rows appear in a truth table for each of these compound propositions?
a) $(q \rightarrow \neg p) \vee(\neg p \rightarrow \neg q)$
b) $(p \vee \neg t) \wedge(p \vee \neg s)$
c) $(p \rightarrow r) \vee(\neg s \rightarrow \neg t) \vee(\neg u \rightarrow v)$
d) $(p \wedge r \wedge s) \vee(q \wedge t) \vee(r \wedge \neg t)$