A) Expanding. We know this because it has a similar effect with sound. When a car goes by the pitch gets deeper and deeper. It's because you're receiving less waves. Same thing for light but instead of a pitch it's light, and the farther spread the waves - the redder, the closer and more contracted - the bluer
Distance is the total length covered = 2m + 3m = 5m
Displacement is his distance from original position.
Displacement = 2m + (-3)m. Representing the 3m walked back as -3.
Displacement = 2m - 3m = -1m.
So his displacement is 1m behind his original starting point.
Answer:
F=84.68 N
Required force increases
Explanation:
By the equation

By newton's second law :

When the mass increased the force increases as the equation.
F=ma