I have two problems. I have filled in most of the information that is asked but I can't seem to figure out a part for each problem. Please Help. Problem 1: 1. The problem statement, all variables and given/known data At a NASA research center free-fall research is performed by dropping experiment packages from the top of an evacuated shaft 146 m high. Free-fall imitates the so called microgravity environment of a satellite in orbit. a) what is the max time interval for free fall if an experiment package were to fall the entire 146 m? 5.45 s [correct] b) Actual NASA specs allow for a 5.24 s drop interval. How far do the packages in 5.24 s? 135m [correct] c) What is their speed at 5.24 s? 51.5 m/s [correct] d) What constant acceleration would be required to stop an experiment package in the distance remaining in the that shaft after its 5.24 fall? 121 m/s^2 [incorrect] 2. Relevant equations Kinematic equations 3. The attempt at a solution Presumably, since the shaft is 146 m tall and the package has already fallen 135 m there are 11 m left for the package to stop. deltaX = 11 m : Vi = 51.5 m/s : Vf = 0 m/s this information should be enough to calculate Ax for the second part of the problem but Webassign says my answer is wrong. Any ideas guys? Problem 2 1. The problem statement, all variables and given/known data An inquisitive physics student and mountain climber climbs a 48.0 m cliff that overhangs a calm pool of water. He throws two stones verticall downwar, 1.00 s apart and observes that they cause a single splash. The first stone has an initial speed of 1.92 m/s downward. Assume the downward direction is positive. (a) How long after release of the first stone do the two stones hit the water? 2.93 s [correct] (b) What initial velocity must the second stone have if they are to hit simultaneously? 16.1 m/s [incorrect] (c) What is the speed of each stone at the instant the two hit the water? first stone 30.7 m/s [correct] second stone 34.62 m/s [correct] 2. Relevant equations Kinematic equations 3. The attempt at a solution This seems like a pretty straightforward problem but I can't seem to get question B right even though I used the value for question B to get the correct answer for question D.