(b) For first vessel, number of moles
$n_{1} = \frac{m_{1}}{M_{1}} = \frac{32}{32} = 1$
Volume=$V$, Temperature=$T$
$\therefore\ \ \ \ \ \ \ \ \ \ \ \ \ \ p_{1}V = RT$ ..(i)
For second vessel number of moles
=$n_{2} = \frac{m_{2}}{M_{2}} = \frac{4}{2} = 2$
Volume=$V$, Temperature=2$T$
$\therefore\ \ \ \ \ \ \ \ \ \ \ \ \ \ p_{2}V = 2R(2T)$ ...(ii)
From Eqs. (i) and (ii),
$p_{2} = 4p_{1} = 4\ p$