For the first$-$order formula $=->((()()=)(()()=))$

$,$ choose ALL that apply.

Question $3$Answer

a$.$

An abstraction is $($p$->($r$$q$))$

b$.$

This is a tautology

c$.$

There are two occurrences of z$,$ all of which are bound

d$.$

This is an axiom of predicate logic