2- A copper fin with a conductivity of k=401 [W/m-K] a circular constant cross-sectional area (diameter D= 2 (cm])
is used to enhance the heat transfer rate. If $T_b$= 80 (C), $T_o$=20 (C), h= 30 [W/m2-K), and the fin is 20 [cm] long,
calculate the heat transfer rate from this fin in [W].
a) 23.18 [W]
b) 0.5655 [W]
c) 0.4707 [W]
d) 19.3 [W]