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Que. The mean thermal conductivity evaluated at the arithmetic mean temperature is represented by
a. km = k0 [1 + β (t1 – t2)/2].
b. km = k0 [1 + (t1 + t2)/2].
c. km = k0 [1 + β (t1 + t2)/3].
d. km = k0 [1 + β (t1 + t2)/2].
Correct Answer:km = k0 [1 + β (t1 + t2)/2].
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