When air expands adiabatically (without gaining or losing heat), its pressure $P$ and volume $V$ are related by the equation $PV^{1.4}=C$ where $C$ is a constant.

Suppose that at a certain instant the volume is 380 ${\rm cm}^3$, and the pressure is 89 kPa (kPa = kiloPascals) and is decreasing at a rate of 8 kPa/minute. At what rate is the volume increasing at this instant?

The volume is increasing at ${\rm cm}^3{\rm /min}$.