Suppose the bent part of the frame of the previous problem has a

Suppose the bent part of the frame of the previous problem has a thermal conductivity of 780 J m-1s-1°C-1 whereas it is 390 J m-1s-1°C-1 for the straight part. Calculate the ratio of the rate of heat flow through the bent part to the rate of heat flow through the straight part.
(a) 12/7
(b) 6/7
(c) 24/7
(d) 7/12

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