Question

Check this please :D

Which of the following three statements used to describe work are true:
i)Work is done only if an object moves through a distance
ii)Work is done only if energy is transferred from one form to another
iii)Work is done only if a force is applied

In which of the following situations does an object have both kinetic and potential energy?
a)A plane is flying at the height of 3 km
b)A rock is perched at the top of a cliff
c)A puck slides across the ice
d)A book rests on a shelf

Make a statement about the IMA of pliers.

I'm guessing 1 is I,II and III
2 is a)
and I'm stuck on 3


Thanks!