A cylindrical can has radius r and height h, both changing with time. At an instant when r=3 cm and h=10 cm, the radius increases at 0.10 cm/s and the height increases at 0.20 cm/s. What is the instantaneous rate of change of the can’s volume?
a) 6π cm3/s
b) 12.9π cm3/s
c) 7.8π cm3/s
d) 1.8π cm3/s