Answer:
The force required to move the quarterback with linebacker is <u>1215 N</u>
Explanation:



Using Newton's second law, it is established that F = Ma
Where F is net force acting on the system, a is the acceleration and M is mass of the two object 
Now consider both
as a system, so net force acting on the system is 
Substitute the given values in the above formula,


Force = 1215 N
<u>1215 N </u>is the force required to move the quarterback with linebacker.
Answer is A. Because the telescope are use in night
Yes, it is diffusion !
Diffusion is the process in which gas, through random movement of particles, tends to fill up the whole volume of the container in which it is placed. So a similar process would lead the smoke, which is in form of gas (or light particles), to fill in the whole room in which it is contained.