Answer: 
Explanation:
The equation to calculate the center of mass 
of a particle system is:
In this case we can arrange for one dimension, assuming the geometric center of the Earth and the ladder are on a line, and assuming original center of mass located at the Earth's geometric center:
Where:
is the mass of the Earth
is the mass of 1 billion people
is the radius of the Earth
is the distance between the center of the Earth and the position of the people (2 m above the Earth's surface)
This is the displacement of Earth's center of mass from the original center.
Answer:
Mercury
Explanation:
Mercury is the closest planet to the sun followed be Venus. Though Mercury is the closest Venus is actually the hotest planet
Vf = 0 + 3.5•8.7
= 30.45 m/s
B. velocity at position x, velocity at position x=0, position x, and the original position
In the equation
= 
+2 a x (x - x₀)
= velocity at position "x"
= velocity at position "x = 0 "
x = final position
= initial position of the object at the start of the motion
