Which pair of concepts are closely related?
O A. radiation and inertia
B. electric and magnetic forces
C. friction and gravity
D. entropy and momentum

I believe it would be C. friction and gravity

Explanation:

They both deal with pulling/pushing objects.

here we know that ball will drop down by total distance 3.2 m

so here we know that

now using kinematics

now in the same time it will cover horizontal distance of 0.75 m

so speed of the ball will be

when heated, the valance electrons increased their speed and transferred the heat from electron to electron.   i just took the test.