A 1.75 inch (diameter) foam ball weighs 0.01 lb (density = 0.776 lbm/ft^3). The ball is dropped out of an airplane 10,000 ft above the ground. Assume density (0.075 lbm/ft^3), viscosity (1.21x10^-5 lbm/fts), and temperature (68 F) of the air are constant from the ground to the airplane level.

a) Calculate the terminal velocity of the ball.

b) Calculate the drag force on the ball when it is at its terminal velocity.