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The air inside a certain residential unit is maintained at 25∘C. On a certain day, the outside air temperature is found to be 1∘C. Estimate the rate of heat loss (in W) through a double pane window 1.5 m×2 m constructed of two 4.1 mm thick glass plates with a 5.8 mm gap between the two. The gap is filled with air which may be assumed to be stationary (conduction being the only mode of heat transfer). The convection coefficients on the two sides of the window are 5 and 20 W m−2 K−1, respectively. The conductivities of glass and air are 1.4 and 0.025 W m−1 K− 1 , respectively.