You're watching a movie and all of a sudden the main character slips and pushes the cake he was holding into the ground. The equal but opposite reaction to the cake hitting the ground is... A. The ground pushing against the main character
B. The cake pushing against the main character
C. The main character pushing against the cake
D. The ground pushing against the cake

You have been hired to design a spring-launched roller coaster thatwill carry two passengers per car. the car goes up a 10-m highhill, then descends 15m to the track's lowest point. you'vedetermined that the spring can be compressed a maximum o 2.0m andthat a loaded car will have a maximum mass of 400kg. for safetyreasons, the spring constant should be 10% larger than the minimumneeded for the car to just make it over the top. a) what spring constant (k) should you specify ? b) what is the maximum speed of a 350 kg car if the spring iscompressed the full amount.