A rail-gun tires a tungsten projectile horizontally with an exit muzzle velocity of 1 500 m/s. The horizontal acceleration at the projectile is given as ax = -40vx2+ 125000vx - 96900000 where vx, = horizontal velocity. The muzzle is 50 meters off the ground. At what distance, in meters, from the muzzle will the projectile strike the ground if the ground remains level? Do not neglect the effects due to gravity.