d
$p \propto \frac{1}{\sqrt{V}}$
If volume becomes $4$ times than $(p)$ will remain half
$V \propto \frac{T}{p}$
$\therefore V p^{2}=$ constant
$\therefore\left(\frac{T}{P}\right) p^{2}=$ constant
or $p T=$ constant
or $p \propto \frac{1}{T}$
i.e. $(p- T)$ graph is a rectangular hyperbola. If $(p)$ is halved than $(T)$ will becomes two times.