A 50 kg car collided with a tree on the road at a speed of 50 m/s and fell into a ditch 3 seconds after reversing at a speed of 10 m/s. If the depth of the hole is 10 times the ratio of the last minute velocity to the initial speed of the vehicle , then if a 0.1 kg ball is thrown down from this height at a speed of 10 m/s, a 0.5 kg mass rat for the momentary velocity before touching the ground .What speed will be gain tha rat