$(\sim (\sim p)) \wedge q$ is equal to .........

Negation of $p \wedge (\sim q \vee \sim r)$ is -

Which of the following statements is correct?
$(a)$ $S_1: (p \wedge q) \equiv \sim(p \rightarrow \sim q)$
$(b)$ $S_2: (p \wedge q) \wedge (\sim p \vee \sim q)$ is a tautology
$(c)$ $S_3: [p \wedge (p$ $\rightarrow \sim q)]$ $\rightarrow q$ is a contradiction
$(d)$ $S_4: p$ $\rightarrow (q$ $\rightarrow p)$ is a contingency

Let $p$ and $q$ stand for the statements "$2 \times 4 = 8$" and "$4$ divides $7$" respectively. Then the truth values of the following biconditional statements are:
$(i)$ $p \leftrightarrow q$
$(ii)$ $\sim p \leftrightarrow q$
$(iii)$ $\sim q \leftrightarrow p$
$(iv)$ $\sim p \leftrightarrow \sim q$

Write the contrapositive and converse of the following statement:
"You cannot comprehend geometry if you do not know how to reason deductively."

The negation of the statement " $72$ is divisible by $2$ and $3$ " is