Hi there hoping a Physics tutor can provide me some help and knowledge on 6-9. Quite lost in this circular motion unit so anything helps, thanks a ton!

UJI' 6. How rituch would a 90 kg astronaut weigh on a large asteroid (5.34 x 1016 kg) if the radius of the asteroid was 1,200 km? 7. A spaceship on the moon has a mass of 5,200 kg and weighs 8320 N. If the mass of the moon is 7.35 x 1022 kg, then what is the radius of the moon? - l) 8. Two identical 6 kg balls have a 1.4 x 107 N gravitational force on each other. What is distance between v the two balls? 9. What is the size of the gravitational eld of the earth (5.98 x 102'- kg) at location 120 km above the surface (Earth's radius is 6,380 km)