A window has heavy curtains in front of it. At night the curtains are closed to minimise heat loss. During the day the curtains are pulled aside exposing the glass window. How much heat is lost through the 1.0 m 1.0 m square glass window pane that is 4mm thick when the inside temperature is 20 degree C and the outside temperature is -6 C (negative 6.0) in 12 hrs? ( 1m = 100 cm) (1m = 1000mm)