I believe the answer for 1) is
PEgrav = mass • g • height
PEgrav = m *• g • h
1. B
2. A
3. B
4. C
5. heterogeneous
6. element
7. do
8. true
9. true
10. true
To solve this problem it is necessary to apply the equations related to the conservation of momentum.
This definition can be expressed as

Where
= Mass of each object
= Initial Velocity of each object
= Final velocity
Rearranging the equation to find the final velocity we have,

Our values are given as

Replacing we have,


Therefore the final velocity is 6.5m/s
<span>At this distance, and with an orbital speed of 24.077 km/s, Mars takes 686.971 Earth days, the equivalent of 1.88 Earth years, to complete a orbit around the Sun. This eccentricity is one of the most pronounced in the Solar System, with only Mercury having a greater one (0.205).
686.971 rounds to 687
HOPE I HELPED!</span>