I have a rectangular slab of aluminum that is in contact with a rectangular slab of copper and both slabs are 5.00 cm x 15.0 cm in area. The thickness of the copper is 1.00 cm thick and the thickness of the aluminum is 1.50 cm thick. One face of the composite slab is at 20.0 Celsius while the other is at 80.0 Celsius. In 1 hr timeframe, how much energy would flow from one face to the other?