Find a compound proposition involving the propositional variables p,q,r, and s that is true when exactly three of these propositional variables are true and is false otherwise.

SolutionStep 1In the Question it is given that there are four propositional variable namely as p,q,r and s respectively.Case 1 :Consider the propositional variable p be false and other three will be true ( p q r s)Step 2Case 2 :Consider the propositional variable q be false and other three will be true. ( p q r s)Step 3Case...