Steel rods ( = 7832 kg/m 3 , c p = 434 J/kgK, and k = 63.9

Steel rods (ρ = 7832 kg/m³, c_p = 434 J/kg·K, and k = 63.9 W/m·K) are heated in a furnace to 850°C and then quenched in a water bath at 50°C for a period of 40 seconds as part of a hardening process. The convection heat transfer coefficient is 650 W/m²·K. If the steel rods have diameter of 40 mm and length of 2 m, determine their average temperature when they are taken out of the water bath.