Answer
The temperature is changing at a rate of $-0.24~K/min$
Work Step by Step
$PV = nRT$
$nR~\frac{dT}{dt} = P\frac{dV}{dt} + V\frac{dP}{dt}$
$\frac{dT}{dt} = \frac{P\frac{dV}{dt} + V\frac{dP}{dt}}{nR}$
$\frac{dT}{dt} = \frac{(8.0)(-0.15) + (10)(0.10)}{(10)(0.0821)}$
$\frac{dT}{dt} = -0.24~K/min$
The temperature is changing at a rate of $-0.24~K/min$