In an experiment in physics class, a model solid-fueled rocket is fired vertically with an acceleration of 5 m/sec2 for 7 seconds. After that time, it's fuel is exhausted and it continues upwards as a free fall particle. (Take upwards to be the positive direction.) a) What is the maximum altitude the rocket reaches? b) What is the rocket's acceleration 8.5 seconds after launch? c) What is the total time of flight? d) What is the rocket's total displacment during the entire flight? I'm only stuck on letter a right now, but if I need further help, I'll let you guys know. For part a, what I tried doing is using this equation, x-x0=vo(t)+(1/2)a(t)^2 where x0=0 vo=0 a=5 m/sec^2 t=7 I get x= 122.5 meters. Computer won't take it, so I'm scratching my head to no end. Any ideas to help me get started?