A stainless-steel billet (6 in. diameter, 1 ft long) is passing through a 20-ft-long heat-treating furnace. The initial billet temperature is 200°F, and it must be raised to a minimum temperature of 1500°F before working. The heat-transfer coefficient between the furnace gases and the billet surface is 15 Btu/h ft2 °F, and the furnace gases are at 2300 °F. (a) (3 pts) Draw a schematic of the problem. (b) (2 pts) State assumptions if you need to make any (c) (20 pts) At what minimum velocity must the billet travel through the furnace to satisfy these conditions?