A cylindrical copper heating element 2 ft long and 1/2 in diameter is immersed in water. The system pressure is maintained at 1 atm and the tube surface is held at 280 F. If the cylinder described were initially heated to 500 F, how long would it take for the center of the cylinder to cool to 240 F if it were constructed of a. copper? b. brass? c. nickel? Please explain all the steps!