Grains of sands are falling and they form a cone with volume,V=1/3πr^2
When the radius of the base of the cone is 10m, the rate at which the radius is increasing is 2cm/s while the rate at which the height is increasing is 1cm/s.
Calculate the rate of change of the volume of the cone at this instant.
There is no angle, no value of height I can plug in, at this point I'm pretty sure that this question is missing some vital information.