Answer:
0.002833 sec
Explanation:
Speed of light in vacuum is 
Given distance = 850 km = 850×1000=850000 m
We have to calculate the time that light take to travel the distance 850 km
Time 
So the time taken by light to travel 850 km is 0.002833 sec
Answer:
The finger has to be placed at 5.25cm
Explanation:
The steps and appropriate formula in musical instrument is as shown in the attachment.
I think the force of spinning it can only hold for so long and because of gravitys pressure.(i hope i helped) :)
B, the acceleration due to gravity is 9.8m/s/s regardless of mass
Allied is the right answer, ig.