Just 3 more questions....
1. If circular speed at 1 AU from the Sun is 30 km/s. What is the circular speed at 20 AU?
2. The acceleration of a 4 kg body to which an unbalanced 18 N force is applied
3. The acceleration of gravity on Mars is 0.38 Earth gravities. How much would a dog that weighs 80 N on Earth weigh on Mars?