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A brick wall $\left(k=0.9\displaystyle{\frac{W}{m.k}}\right)$ of thickness $0.18$ $m$ separates the warm air in a room from the cold ambient air. On a particular winter day, the outside air temperature is $−5^\circ C$ and the room needs to be maintained at $27^\circ C$. The heat transfer coefficient associated with outside air is $20\displaystyle{\frac{W}{m^2k}}$. Neglecting the convective resistance of the air inside the room, the heat loss, in $\displaystyle{\frac{W}{m^2}}$, is

  1. $88$
  2. $110$
  3. $128$
  4. $160$
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