What is the temperature of the wall of the steel ball cooled in water for 1.5 hours? Given for the system include: . . h= 2.02 Btu/h ft? F k = 24 Btu/h ft Cp = 0.09 Btu/lba F T. = temperature is held constant at 200F r = 2 inches P = 490 lb/ft T.=800F . . 1) Determine the Ng (Biot number for this problem) Reynolds's Biot Number is given by the following equation: hxi X1 r X1 and x2 = (Remember x is also known as Lc) ) NBi = k 3 2) Then calculate Ts (temperature at the surface of the steel ball wall)