A vertical conveyor has sprocket A as the driver, and sprocket B turns freely. The bodies to be lifted are pushed onto the conveyor belt by a plunger C and are taken off from the conveyor at D as shown in the diagram. If the belt runs at $2$m$/$s and the bodies being transported each has a mass of $0\mathrm{.}25$kg$,$ what average torque is required by the driving sprocket A$?$ On the average, $40$ bodies are on the conveyor at any time.$($ANS$.14\mathrm{.}76$ N$-$m$)$