Answer:
The bag weighed a ton.
Explanation:
A hyperbole is an exaggeration about the extent or seriousness of something to better make a point.
In this case, saying "The bag weighed a ton" is an exaggeration, because it is very unlikely that a bag actually weighed a ton. However, it is used to help convey the point to the reader, and the point is that the bag was very, very heavy.