At some point during construction, the International Space Station had a
mass of 235,565 kg. When it orbited the Earth at an altitude of 400,000 m,
what was the approximate gravitational force on the Station due to Earth's
gravity? (Recall that Earth has a radius of 6.37 × 106 m, it has a mass of 5.97
x 1024 kg, and G = 6.67 x 10-¹1 Nm²/kg².)