1) A 4.0 g bullet is fired from a 50kg gun with a speed of 600m/s. What is the speed of recoil of the gun? 2) A 6.6 x 104 N car traveling with a speed of 30km/h strikes an obstruction and is brought to rest in 0.10 s. What is the average force on the car? 3) A 2.0 kg ball B travelling with a speed of 22 m/s overtakes a 4.0kg ball A traveling in the same direction as the first, with a speed of 10m/s. If the coefficient of restitution is 0.80, find the speeds of the two balls after the collision