At the surface of Earth, an astronaut has a gravitational mass of 80 kg at a location where the acceleration due to gravity is 10 m/s2. What is the force of gravity on the astronaut at a location one Earth radius above Earth's surface? Question 14 options: 40 N [toward the centre of Earth] 200 N [toward the centre of Earth] 400 N [toward the centre of Earth] 800 N [toward the centre of Earth]