You have been hired to design a spring-launched roller coaster that will carry two passengers per car. the car goes up a 10-m -high hill, then descends 15 m to the track's lowest point. you've determined that the spring can be compressed a maximum of 2.4 m and that a loaded car will have a maximum mass of 430 kg . for safety reasons, the spring constant should be 15 % larger than the minimum needed for the car to just make it over the top. what is the maximum speed of a 330 kg car if the spring is compressed the full amount?