A circut board with a length of 120 mm and a width of 120 mm is cooled by air at the atmospheric pressure and temperature t= 290k flowing witha velocity of v= 2m/s past the top surface from the wind tunel test under the same flow conditions, the average frictional drag coeficent on the upper surface is c= 0.0266. when in servie the average surface temperature of the circut board must not exceed the ambient air temperature by more than 20c. a calculate the average convection heat coefficient for the top surface. you must use an appropriate momentum heat tranfer analoly to recieve credit . b detemine the allowable power dissipated from the top surface. c why did you chose the relationship analogoy is it the best chose?
Options:

a) Nusselt Number - Reynolds Number relationship
b) Stanton Number - Prandtl Number relationship
c) Reynolds Number - Grashof Number relationship
d) Prandtl Number - Nusselt Number relationship