The radius of the base of a cylinder is increasing at a rate of $1$ meter per hour and the height of the cylinder is *decreasing* at a rate of $4$ meters per hour.
At a certain instant, the base radius is $5$ meters and the height is $8$ meters.
**What is the rate of change of the volume of the cylinder at that instant (in cubic meters per hour)?**
[[☃ radio 1]]
*The volume of a cylinder with base radius $r$ and height $h$ is $\pi r^2h$.*