The correct answer is
c) Neither person is correct because light does not change frequency when it travels through different media
In fact, light changes both wavelength and speed when it travels through different media, but the frequency remains the same.
I- wym incorrect answer i-
let the distance of pillar is "r" from one end of the slab
So here net torque must be balance with respect to pillar to be in balanced state
So here we will have

here we know that
mg = 19600 N
Mg = 400,000 N
L = 20 m
from above equation we have



so pillar is at distance 10.098 m from one end of the slab
Answer:
The momentum makes it worse.
Explanation:
The momentum of vehicles running at faster speeds is very high and causes a lot of damage to the vehicles.