The gas phase reaction A $+$ B $->$ R was performed in a reactor equipped with a pressure gauge. The test started with an equimolar mixture of A and B with the following results at $100\backslash$deg C$.$

Calculate the time required to achieve a $75\%$ conversion if the reaction is carried out at a total pressure of $2$ atm, $100\backslash$deg C$,$ and a feed consisting of:

A$,30\%$

B$,60\%$

Inert, $10\%$