A 2.5 x 2.5 m steel sheet 1.5 mm thick is removed from an annealing oven at a uniform temperature of 425?C and placed in a large room at 20?C in a horizontal position.(a) Calculate the rate of heat transfer from the steel sheet immediately after its removal from the furnace, considering both radiation and convection.(b) Determine the time required for the steel sheet to cool to a temperature of 60?C.GIVENHorizontal steel sheet in airSheet dimensions = 2.5 m x 2.5 m x 0.0015 mSheet initial temperature (Tsi) = 425?C = 698 KAir temperature (T??) = 20?C = 293 KASSUMPTIONSThe room behaves as a black body at T??The steel sheet behaves as a black body (ε= 1.0)Heat transfer takes place from both top and bottom of the sheetThe steel is 1% carbon steelHeat transfer from the edges of the plate isnegligible

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T-= 293 K Tu= 698 K 0.0015 m Alr 2.5 m