A 0.289-kg coffee mug is made from a material that has a specific heat capacity of 990 J/kg C° and contains 0.304 kg of water. The cup and water are at 23.9 °C. To make a cup of coffee, a small electric heater is immersed in the water and brings it to a boil in two minutes. Assume that the cup and water always have the same temperature and determine the minimum power rating of this heater.