A 45 kg box is sitting on a window ledge 2.0 m above the ground. What is the potential energy of the box?

Explanation:

The potential energy of a body can be found by using the formula

PE = mgh

where

m is the mass

h is the height

g is the acceleration due to gravity which is 10 m/s²

From the question we have

PE = 45 × 10 × 2

We have the final answer as

Hope this helps you

h let me think

i believe you are right for all except the 3rd ( look at sqdancefan his answer is much better)