Which of the following statement is true
$ \sim (p \leftrightarrow \sim q)$ is tautology
$ \sim (p \leftrightarrow \sim q)$ is equivalent to $p \leftrightarrow q$
$(\,p\, \wedge \, \sim q)$ is a fallacy
$(\,p\, \wedge \, \sim q)\, \wedge \,( \sim p\, \wedge \,q)$ is a tautology
Which one of the following, statements is not a tautology
Let $r \in\{p, q, \sim p, \sim q\}$ be such that the logical statement $r \vee(\sim p) \Rightarrow(p \wedge q) \vee r \quad$ is a tautology. Then ' $r$ ' is equal to
The statement $(\sim( p \Leftrightarrow \sim q )) \wedge q$ is :
Negation of $(p \Rightarrow q) \Rightarrow(q \Rightarrow p)$ is
The negation of the statement
"If I become a teacher, then I will open a school", is