D / Question 12 l V You are an astronaut in a small planet with mass M=7x1020 kg and radius R=1500 km. The planet is not rotating with respect to any axis. You want to build a machine that throws a small baseball radially upwards to a maximum height of 2500 km above the surface and then falls back to the ground What initial speed must your machine impart on the baseball? Express your answer in m/s. Note that the drawing is obviously not to scale. There is no atmosphere on this planet so you can neglect any friction effects