How much is the work done on the block by A 147 g bullet is ?red from a rifle having a barrel 0.671 m long. Assuming the origin is placed where the bullet begins to move, the force exerted on the bullet by the expanding gas is F = a + b x - c x^2, where a = 7800 N, b = 10400 N/m, c = 22200 N/m^2, with x in meters. Determine the work done by the gas on the bullet as the bullet travels the length of the barrel.