3. If the specific heat of iron = 0.46 J/g Cº, how much heat is needed to warm 50 g of Iron from 20° C to 100°C?

Suppose that a cylindrical tank 6 meters high with a radius of 2 meters is filled to the rim with water. the tank is buried so that the top of the tank is 1 meter below ground level. the space above the tank is not filled with water. calculate how much work needs to be done by a pump to pump the water out of the tank up to ground level. (the water weighs 9,800 newtons per cubic meter.)