One face of a furnace wall is at 1030°C and the other face is exposed to room temperature (30°C). If the thermal conductivity of furnace wall is 3 W. m- 1. k-1 and the wall thickness is 0.3 m, the maximum heat loss (in W/m) is

A. 100

B. 900

C. 9000

D. 10000

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