A two-stage rocket is launched straight up from rest. It accelerates at 25.8 m/s/s for 3.91 seconds during the first stage. It accelerates at 15.7 m/s/s for 4.30 more seconds during the second stage. After second stage burnout the rocket comes under the influence of gravity only. Determine its height above launch point (in meters) after 40.86 seconds from launch.