Amachine is rolling a metal cylinder under pressure. the radius of the cylinder is decreasing at a constant rate of 0.05 inches per second and the volume, v, is 128pi cubic inches. at what rate is the length, h, changing when the radius, r, is 1.5 inches? note: v=pi(r^2)h

hi, as above this is the problem i am doing. there is no answer given to check so i was wondering about a couple of things:

is volume assumed to be a constant in this problem?

is the height change decreasing (negative rate) or increasing (positive rate) in the final answer?

i worked out dh/dt to be 512/135 in./s