Planet Zero has a mass of 5.0 1023 kg and a radius of 2.0 106 m. A space probe is launched vertically from the surface of Zero with an initial speed...

Planet Zero has a mass of 5.0  1023 kg and a radius of 2.0  106 m. A space probe is launched vertically from the surface of Zero with an initial speed of 4.0 km/s. What is the speed of the probe when it is 3.0  106 m from Zero’s center?