A sphere of radius rrr is expanding. dV/dt=10dV/dt = 10dV/dt=10. How fast is dr/dtdr/dtdr/dt increasing when r=5r=5r=5?
1/(10π)1/(10\pi)1/(10π)
1/(5π)1/(5\pi)1/(5π)
1/(2π)1/(2\pi)1/(2π)
1/π1/\pi1/π