$7.$ For each of the following expressions, write down an expression that is

equivalent to them but does not contain an implication $($i$.$e$.,$ no $$ symbol$)$:

I. P $($Q V R$)$

II$.($P $$ Q$)$ R

III. P $($Q $$ R$)$

IV$.($P $$ Q$)($R $$ Q$)$