Question

A spherical snowball is melting in such a way that its radius is decreasing at rate of 0.1 cm/min. At what rate is the volume of the snowball decreasing when the radius is 14 cm.

Answer 1

V=(4/3)pir^3
take derivitive
dV/dt=4pir^2 (dr/dt)
dr/dt=-0.1
r=14
dV/dt=4pi14^2*-0.1
dV/dt=-78.4pi cm/min