Consider a 300 mm x 300 mm window in an aircraft. For a temperature difference of 80°C from the inner to the outer surface of the window, calculate the heat loss through L = 10-mm-thick polycarbonate, soda lime glass, and aero-gel windows, respectively. The thermal conductivities of the aero-gel and polycarbonate are kag = 0.014 W/m · K and k pc = 0.21 W/m · K, respectively. Evaluate the thermal conductivity of the soda lime glass at 300 K. If the aircraft has 130 windows and the cost to heat the cabin air is $l/kW · h, compare the costs associated with the heat loss through the windows for an 8-hour intercontinental flight.