Motorcycle helmets are padded to give the rider the protection they require in case of accidents. Any hit to the head is absorbed by the padding and the rider is saved from any kind of fatal injury. Whenever a motorcycle rider falls from his motorcycle, there is every possibility that the head will hit the ground first. If the padding was not there, then the rider would get the direct impact of hitting. As most of the pressure of the hit gets absorbed by the inner padding of the helmet, so the rider is saved from the fatal accident. It does not mean that the driver will not have minor injuries but by all chance his life would be saved.
Answer:
B. 0.16 m
Explanation:
The vertical distance by which the player will miss the target is equal to the vertical distance covered by the dart during its motion.
Since the dart is thrown horizontally, the initial vertical velocity is zero:

While the horizontal velocity is

The horizontal distance covered is

Since the dart moves by uniform motion along the horizontal direction, the time it takes for covering this distance is

along the vertical direction, the motion is a uniformly accelerated motion with constant downward acceleration g=9.8 m/s^2, so the vertical distance covered is given by

Efficiency = (energy that does the job) / (total energy used)
= (45 J) / (120J)
I think you can handle the division.