NASA launched a flying saucer to the top of the stratosphere. The plan was for the flying saucer to reach a height of 50 kilometer before entering the next phase of launch to the planet mars using rocket in space. The saucer initially accelerated from rest to a steady speed of 20000 miles per hour. If the parachute carrying the saucer reached a steady speed of 20000 miles per hour at a height of 0.5 kilometer from the surface of the earth, find what was the acceleration achieved by the saucer carried by the parachute. Find how much time did it take for the saucer to reach the edge of stratosphere at a height of 50 kilometer?