The tension in the string with friction would be the biggest because of the involvement of the force of gravity. This would result in that the friction force that is acting on the system. There is no friction in the frictionless system, and only the force of gravity is relevant.
Answer:
c) L³/T³
Explanation:
If t stands for time, the units are:
(V) = L³, (t) = T
The units for the equation:
V(t) = At³
must be:

No, not exactly. They jiggle and tremble and vibrate a lot, but
they always basically stay in very nearly the same place.
It's like if you're allowed to go anywhere you want in your jail cell,
you wouldn't exactly call that "moving about freely".