3. (40 pts) 5000lb oil is being heated in a stirred tank by saturated steam which is condensing in the steam coils immersed in the tank. The tank is well mixed. Temperature of the saturated steam is 267F and the heat transfer rate is given by Q^=dtdQ=hT where Q is the heat transferred in BTU and h is the heat transfer coefficient. Oil initially at 60F enters to the tank at a rate of 1018lb/h and leaves at the same rate. If the energy introduced by the motor is 3hp with 75% efficiency, how long does it take for the discharged oil from the tank to rise from 60F to 90F?(Cpoil=0.5BTU/lb.F and h=291BTU/h.F) (Hint: Reference temperature is Tref=60F )