A company wants to expand the solid propellant manufacturing plant by the addition of more than 1 ton capacity curing furnace. Each ton of propellant must undergo 30 minutes of furnace time including loading and unloading operations. Furnace is used only 80 percent of the time due to power restrictions. The required output for the new layout is to be 16 tons per shift (8hours). Plant (system) efficiency is estimated at 50 percent of system capacity. The number of furnaces required will be
(a) 3 (b) 2 (c) 1 (d) 4