#### Question

Where a, b and c are the inside dimensions and d x is the wall thickness

a.

2/ d x (a b + b c + c a) + 4 (0.64) (a + b +c) + 8 (0.45) d x

b.

2/ d x (a b + b c + c a) + 4 (0.44) (a + b +c) + 8 (0.35) d x

c.

2/ d x (a b + b c + c a) + 4 (0.34) (a + b +c) + 8 (0.25) d x

d.

2/ d x (a b + b c + c a) + 4 (0.54) (a + b +c) + 8 (0.15) d x

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###### Q. The shape factor for complete rectangular furnace is Where a, b and c are the inside dimensions and d x is the wall thickness

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