Answer: 1200pi cubic cm per sec
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Work Shown:
dr/dt = 3 is the rate of change of the radius
V = (4/3)pi*r^3 ..... volume of a sphere
dV/dt = (4/3)*3*pi*r^2*dr/dt ... chain rule
dV/dt = 4*pi*r^2*dr/dt
dV/dt = 4*pi*r^2*3
dV/dt = 12*pi*r^2
dV/dt = 12*pi*10^2 ... plug in r = 10
dV/dt = 1200pi