1.How to find a compound proposition logically equivalent to p--> q using only the logical operator NOR . 2. How many truth tables of compound propositions are there that involve...

a) ∃!xP(x) → ∃xP(x) b) ∀xP(x) → ∃!xP(x) c) ∃!x¬P(x)→¬∀xP(x) I am unable to get any idea how to approach this question ,so plz guide..