CP and CV denote the molar specific heats of a gas at constant pressure and at constant volume respectively. If $\dfrac{\text{C}_P}{\text{C}_V} = \gamma$ and CP – CV = R, then CV is equal to
$\dfrac{\text{R}}{\gamma - 1}$
$\dfrac{\gamma - 1}{\text{R}}$
$\dfrac{\gamma \text{R}}{\gamma - 1}$
$\sqrt{\dfrac{\text{R}}{\gamma - 1}}$