The inner and outer surfaces of a 0.5-cm-thick 2-m 3 2-m window glass in winter are 158C

Question:

The inner and outer surfaces of a 0.5-cm-thick 2-m 3 2-m window glass in winter are 158C and 68C, respectively. If the thermal conductivity of the glass is 0.78 W/m·8C, determine the amount of heat loss, in kJ, through the glass over a period of 10 h. What would your answer be if the glass were 1-cm thick?