What is the cause of buoyant force?

5 kg of material A occupy 20 cm³ whereas 20 kg of material B occupy 90 cm³. Which has the greater density: A or B? Support your answer with calculations.

Define buoyant force. Name two factors on which buoyant force depends.

When a boat is partially immersed in water, it displaces 600 kg of water. How much is the buoyant force acting on the boat in Newton? (g = 10 m s^-2)

State the principle of flotation.