Proving Categorical Quantifier Negations

Prove the following theorems in QL. For this you need only Conditional Proof, the Equivalence Rules, and basic Quantifier Negation Rules.

1. (x)(Sx ⊃ Px)  ≡ ~(∃x)(Sx & ~Px)

2. ~(x)(Sx ⊃ Px) ≡ (∃x)(Sx & ~Px)

3. ~(x)(Sx ⊃ ~Px) ≡ (∃x)(Sx & Px)

4. (x)(Sx ⊃ ~Px) ≡ ~(∃x)(Sx & Px)