A copper block is removed from a furnace at 150∘C and immediately placed into 0.300kg of water at 25∘C in an insulated container. After stirring, the water’s temperature rises to 35∘C. Assuming 5.0% of the thermal energy released by the copper is lost to the surroundings and no phase changes occur, determine the mass of the copper block. (Specific heats: water 4186Jkg−1∘C−1, copper 386Jkg−1∘C−1.)