. Consider the set of connectives consisting of just and , where is an exclusive OR connective: AB is true if and only if A and B have the opposite truth values (one is true and the other one false).

(a) First, show that , form a complete set of connectives by showing how to write formulas equivalent to AB and A using only and .

(b) Now, rewrite the formula (pq) (rp) using only and . First write AB with only and , then use this together with formulas from the previous subquestion to write a formula equivalent to (pq) (rp) using just and as your connectives.