Explanation:
It is given that,
Length of the string, l = 2 m
Mass of the string, 
Hanged mass in the string, 
1. The tension in the string is given by :


T = 1.96 N
2. Velocity of the transverse wave in the string is given by :

m = M/l


v = 28 m/s
Hence, this is the required solution.
50 because that is as fast as a car
The guys before me was almost right. But instead of it being vertical it is horizontal.
The correct answer is B (Inertia)
We define inertia as the resistance to change of the state of motion. That is, a body tends to remain in its state of motion or rests unless an external for acts on it. The quantity depends on the mass of the body. If the body is heavy, it requires a large force to overcome the inertia.