A.
if you have seen a newton's cradle this will make sense.
in order for both of them to travel at the same speed, the balls need to have the same mass and the speed to begin with tocontinue to travel at the same speed because mass can affect the impact of the force on the balls by each other, causing each ball to have different speeds.
The average velocity of Sandy is given by the total distance covered S divided by the total time taken t:

The total distance covered is

while the total time taken is 2 hours + half an hour (for the rest) + 1 hour and half, so

Therefore, the average velocity is
Answer:
15N
Explanation:
According to Newton's Second Law of Motion
F = m*a
mass = m = 5Kg
acceleration = a = 3m/s^2
=> F = 5kg * 3m/s^2
=> F = 15 N
The most widely accepted scientific explanation of the origin of the universe is D. The big bang theory.