A hot-air balloon roughly spherical in shape has a volume of 70,000 ft3 and a weight of 500 lb (including passengers, basket, balloon fabric, etc.). If the outside air temperature is 80 F and the...

A hot-air balloon roughly spherical in shape has a volume

of 70,000 ft3

and a weight of 500 lb (including passengers, basket,

balloon fabric, etc.). If the outside air temperature is 80 °F and

the temperature within the balloon is 165 °F, estimate the rate at

which it will rise under steady-state conditions if the atmospheric

pressure is 14.7 psi.