1. A dentist's chair with a person in it weighs 2000 N. The output plunger of a hydraulic system starts to lift the chair when the dental assistant's foot exerts a force of 37 N on the input piston. Neglecting any difference in the heights of the piston and the plunger, what is the ratio of the area of the plunger to the area of the piston?

A_plunger/ A_piston=

2. A modern-day zeppelin holds 9,760 m³ of helium. Compute its maximum payload at sea level. (Assume the helium and air to be at 0C and 1 atm.) (answer in N)

3. An empty storage tank has a volume of 9,470 ft³. What is the buoyant force exerted on it by the air? (Assume the air is at 0C and 1 atm.) (answer in lb)