Air flows with a mass rate of 0.1 kg/s through an aluminum circular pipe of inner diameter d, 0.15 m and outer diameter do-0.20 m at inlet temperature of 100°c. after traveling l-10 m, the air cools down to 75°c. outside the pipe, heat transfer from the pipe to the surroundings takes place by convection and radiation a to=tsur =20°c and a combined convection and condtuction heat transfer coefficient of 5 w/m2.k a)- calculate the heat loss in watts from the duct over the whole pipe. b)- draw the equivalent thermal circuit and calculate the value of all thermal resistances. c)-determine the heat flux and the duct surface temperature at x=l .