Answer:

this force is
times more than the gravitational force
Explanation:
Kinetic Energy of the electron is given as


now the speed of electron is given as

now we have


now the maximum force due to magnetic field is given as



Now if this force is compared by the gravitational force on the electron then it is


so this force is
times more than the gravitational force
55 Kg has a weight of 55x9.8= 539 N
That is equal to the Normal force.
The static friction = 0.19 x 539 = 102.4 N
This is true. The break handles and brakes are levers and the seat adjustment (raise or lower) is a screw.
Explanation :
Absorption coefficient of a material determines how much sound is absorbed by the material.
To build a soundproof room, Heavy curtains and carpet can be used. They reduce reverberation.
Reverberation means an echoing sound which persists for some time. For example, when we bang on a huge piece of metal, we hear the reverberation even after we stop banging.
Hence, option (A) and (D) are correct.