A hot surface at 80°C in air at 20°C is to be cooled by attaching 10-cm-long and 1-cm-diam...

A hot surface at 80°C in air at 20°C is to be cooled by attaching 10-cm-long and 1-cm-diameter cylindrical fins. The combined heat transfer coefficient is 30 W/m2•°C, and heat transfer from the fin tip is negligible. If the fin efficiency is 0.75, the rate of heat loss from 100 fins is

(a) 325 W

(b) 707 W

(c) 566 W

(d) 424 W

(e) 754 W