A concrete slab is 3m by 8m and has thickness of 15cm. How much heat flows each second through the slab if the difference in temperature between the top and bottom is 10 degrees celsius? Take the thermal conductivity of dense concrete as 1.0 W/(m K). ( There is a wide variation depending on the type of concrete). O 1.6 W 16 KW O 1.6 kW