The statement $\sim[p \vee(\sim(p \wedge q))]$ is equivalent to

The statement $p \rightarrow  (q \rightarrow p)$  is equivalent to

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

Let $\Delta, \nabla \in\{\wedge, \vee\}$ be such that $p \nabla q \Rightarrow(( p \nabla$q) $\nabla r$ ) is a tautology. Then (p $\nabla q ) \Delta r$ is logically equivalent to

Let $\Delta, \nabla \in\{\wedge, \vee\}$ be such that $( p \rightarrow q ) \Delta( p \nabla q )$ is a tautology. Then

The Boolean expression $\left( {\left( {p \wedge q} \right) \vee \left( {p \vee  \sim q} \right)} \right) \wedge \left( { \sim p \wedge  \sim q} \right)$ is equivalent to