A 135 g bullet is fired from a rifle having a barrel 0.590 m long. Assuming the origin is placed where the bullet begins to move, the force (in newtons) exerted by the expanding gas on the bullet is 20000 + 8000x - 22000x2, where x is in meters. (a) Determine the work done by the gas on the bullet as the bullet travels the length of the barrel. (b) If the barrel is 1.25 m long, how much work is done, and how does this value compare to the work calculated in part (a)? For part A, i plugged in .590m into x for the equation of the force, multiplied that by .590 because W = Force x Distance, and since they wanted an answer in kJ i divided by 1000, but it says that my answer is incorrect. Any thoughts?