A spherical helium-filled weather balloon has a radius of 1.10 m.

a.compute the magnitude of the buoyant force on the balloon. (b) the balloon's rubber skin has a mass of 1.20 kg. when released, what is the magnitude of the balloon's initial acceleration if it carries a payload with a mass of 3.52 kg? density of air =1.29 kg/m^3 and density of helium=0.180 kg/m^3