If Qs is heat supplied by the steam and Qf is the heat evolved in the feed, then the overall heat transfer coefficient can be represented as? Here AF = Area of film and AW = Area of wall.

If Qs is heat supplied by the steam and Qf is the heat evolved in the

1.	If Qs is heat supplied by the steam and Qf is the heat evolved in the feed, then the overall heat transfer coefficient can be represented as? Here AF = Area of film and AW = Area of wall.
A.	U = Qf/AW ΔT
B.	U = Qs/AF ΔT
C.	U = (Qs – Qf)/AW ΔT
D.	U = (Qs – Qf)/AF ΔT
Answer» B.