A helium balloon ride lifts up passengers in a basket. Assume the density of air is 1.28 kg/m3 and the density of helium in the balloon is 0.18 kg/m3. The radius of the balloon (when filled) is R = 4.8 m. The total mass of the empty balloon and basket is mb = 120 kg and the total volume is Vb = 0.068 m3. Assume the average person that gets into the balloon has a mass mp = 71 kg and volume Vp = 0.079 m3.

1) What is the volume of helium in the balloon when fully inflated?
2) What is the magnitude of the force of gravity on the entire system (but with no people)?
3) What is the magnitude of the buoyant force on the entire system (but with no people)?
4) What is the magnitude of the force of gravity on each person?