Let the ends of a copper rod 100 cm long be maintained at 0 degrees celsius. suppose that the center of the bar is heated to over 100 degrees. celsius by an external heat source and that this situation is maintained until a steady state results. find the steady state temperature distribution. at t = 0 [after steady state part (a) has been reached], let the heat source be removed. at that the same instant let the end x= 0 be placed in thermal contact with a reservoir at 20 degree celsius, while the other end remains at 0 degree celsius. find the temperature as a function of time u (x, t).