a) Estimate the heating load for a building in a cold climate when the outside temperature is -10C and the air inside is maintained at 20C. The 350 m2 of walls and ceiling are a composite of 1 cm-thick wallboard (k = 0.2 W/m K), 10 cm of vermiculite insulation (k = 0.06 W/m K), and 3 cm of wood (k = 0.15 W/m K). Take the inside and outside heat transfer coefficients as 7 and 35 W/m2 K, respectively. b) If a 2.5 x 10 m shaded wall in the above building is replaced by a window, compare the heat loss through the wall if it is (i) 0.3 cm-thick glass (k = 0.88 W/m K). (ii) double-glazed with a 0.6 cm air gap between two 0.3 cm-thick glass panes. (iii) the original wall.