Answer:
F = GMm / r²
from Newton's law of gravitational attraction
(a) 8927 mi/h
In order to calculate the average speed, we need to convert the time (t=5.0 y) into hours first. In 1 year, we have 365 days, each day consisting of 24 hours, so the time taken is:

The distance covered by the spacecraft is

Therefore, the average speed is just the ratio between the distance covered and the time taken:

(b) 35 minutes (2097 seconds)
The transmitted signals (which is a radio wave, which is an electromagnetic wave) travels back to the Earth at the speed of light:

Since 1 miles = 1609 metres, the distance covered by the signal is

So, the time taken by the signal will be

And since 1 minute = 60 sec, the time taken is

Answer:
Explanation:
Given
mass of disk 
diameter of disc 
Force applied 
Now this force will Produce a torque of magnitude



And Torque is given Product of moment of inertia and angular acceleration 

Moment of inertia for Disc 



I believe the answer is option C 1.8 kg•m/s to the east