A spacecraft is coasting toward Mars. The mass of Mars is 6.4 × 1023 kg and its radius is 3400 km (3.4 × 106 m). When the spacecraft is 7000 km (7 × 106 m) from the center of Mars, the spacecraft's...

A spacecraft is coasting toward Mars. The mass of Mars is 6.4 × 1023 kg and its radius is 3400 km (3.4 × 106 m). When the

spacecraft is 7000 km (7 × 106 m) from the center of Mars, the spacecraft's speed is 3000 m/s. Later, when the spacecraft is

4000 km (4 × 106 m) from the center of Mars, what is its speed? Assume that the effects of Mars's two tiny moons, the other

planets, and the Sun are negligible. Precision is required to land on Mars, so make an accurate calculation, not a rough,

approximate calculation.