Which of the following is a statement

If the Boolean expression $( p \Rightarrow q ) \Leftrightarrow( q *(\sim p ))$ is a tautology, then the Boolean expression $p *(\sim q )$ is equivalent to

If $P$ and $Q$ are two statements, then which of the following compound statement is a tautology?

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

The contrapositive of the statement "If I reach the station in time, then I will catch the train" is 

$( S 1)( p \Rightarrow q ) \vee( p \wedge(\sim q ))$ is a tautology $( S 2)((\sim p ) \Rightarrow(\sim q )) \wedge((\sim p ) \vee q )$ is a Contradiction. Then