A hollow plastic sphere is held below the surface of a freshwater lake by a cord anchored to the bottom of the lake. The sphere has a volume of 0.700 m^3 and the tension in the cord is 900 N .
Part A: Calculate the buoyant force exerted by the water on the sphere.
Part B: What is the mass of the sphere?
Part C: The cord breaks and the sphere rises to the surface. When the sphere comes to rest, what fraction of its volume will be submerged? please show all work.