Two 5 cm diameter, 15 cm long aluminum bars (k = 176 W/m*K) with ground surfaces are pressed against each other with a pressure of 20 atm. The bars are enclosed in an insulation sleeve and , thus heat transfer from both lateral surfaces is negligible. If the top and bottom surfaces of the two-bar system are maintained at temperatures of 150 C and 20 C respectively, determine the rate of heat transfer along the cylinders under steady conditions and the temperature drop at the interface.