Rate of change of momentum = impact force
(m*v-m*u)/t = F
4000*20/t = 80000 (note: v is zero as it stopped)
<span>soo, t = 1 sec</span>
The distance between city a and city b is 833.345 miles.
We know that
1°=60'
The distance of city a from the initial ray is calculated as
x_a=3960*tan45.46°=4024.101 miles
The distance of city b from the initial ray is calculated as
x_b=3960*tan 38.86°=3190.75 miles
Now the distance between city a and b is equal to
4024.101-3190.75=833.345 miles
This is the vertical distance between the cities.
The answer to your question is true.