Can I please get help with B5, question b

BB A car driver travelling at 72 km h\"1 suddenly sees alfallen tree'on the road 40 m ahead. He puts on the brakes to stop before he hits the tree. To put on the brakes requires 0.755 (the reaction time of the driver), after which the retardation is 8ms'2. What is the total stopping time? How far does he travel before the brakes are applied? What is his total stopping distance? if he subsequently travels at twice the speed, how far ahead should he be able to see clearly for safety? (Assume the deceleratidn is the same.) (3.25 s; 15 m; 40 m; 130 m) B6 A train moving between two stations 1100m apart accelerates uniformly for 40 s, and then moves at constant speed until the brakes are applied. If it comes to rest after 305 and the whole journey takes 90 5, find the maximum speed, the acceleration, and the retardation. (20 m S\": 0.5 m 5'2; 0.67 m 52) B? Suppose you are visiting a planet in a distant part of the galaxy. To determine the acceleration due to gravity on this planet, you drop a rock from a height of 55 m. The rock strikes the around 1.95 later. How many times greater is the acceleration due to