Answer:
electric potential energy=

so the electric potential energy and distance(r) are inversely proportional.
then, the greatest energy occur in the smallest distance b/n the two balloon.
Answer:
W = 0
Explanation:
We are given with, a construction worker is carrying a load of 40 kg over his head and is walking at a constant velocity. He travels a distance of 50 m.
The work done by an object is given by :

F = ma
So,

m is mass
a is acceleration
d is displacement
The worker is moving with constant velocity, its acceleration will be 0. So, the work done by the worker is 0.
2.8 kg .............is the mass of a 1.2 N book.