Log mean temperature difference (LMTD) cannot be used, if

1.	Log mean temperature difference (LMTD) cannot be used, if
A.	heat transfer co-efficient over the entire heat exchanger is not constant.
B.	there exists an unsteady state.
C.	the heat capacity is not constant and there is a phase change.
D.	none of these.
Answer» E.

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Log mean temperature difference (LMTD) cannot be used, if

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