Given two compound statements and Y$,$ their truth tables are said to be equal if the entries of each TOW of their final columns match; assuming the truth values for the propositional variables also match for each row $.$ The truth tables are different otherwise For example, the truth tables for P $^$ Q and Pv Q are different $,$ while the truth tables for P $^$ Q and $($P$^$Q$)$ v $($P$^-$P$)$ are equal:

Q P$^$ Q Q Pv Q Q $7$P P$^-$P P$^$Q $($P$^$Q$)$ V $($P$^-$P$)$ T T F F F FF f IVF F

How many different truth tables of compound statements are there that involve the statements P and Q$?$ Briefly explain why: