We have F = kx or ma = kx where m and k are constants. Therefore, if x is halved, a must be halved too.
You said that she's losing 1.9 m/s of her speed every second.
So it'll take
(6 m/s) / (1.9 m/s²) = 3.158 seconds (rounded)
to lose all of her initial speed, and stop.
As per above given data
initial velocity = 19.3 km/s
final velocity = - 18.8 km/s
now in order to find the change in velocity




Part b)
Now we need to find acceleration
acceleration is given by formula

given that


now the acceleration is given as


so above is the acceleration
Answer:
The moon is 400x smaller but it's also 400x closer so it looks the same size even though it's not
Explanation: