(c) From $p_{1}V_{1}^{\gamma} = p_{1}V_{2}^{\gamma}$
$\frac{p_{2}}{p_{1}} = \left( \frac{V_{1}}{V_{2}} \right)^{\gamma} = \left( \frac{\rho_{2}}{\rho_{1}} \right)^{\gamma}$
$= (32)^{7/5} = \left( 2^{5} \right)^{7/5} = 2^{7} = 128$
$\therefore\ \frac{P_{2}}{P_{1}} = \frac{P^{\ }}{P} = 128$