At a construction site, workers are moving dirt from a pile to fill a hole. The function graphed models the volume of dirt y in cubic feet remaining in the pile after x hours.

Choose the best answer regarding the slope.
Question 4 options:

The slope indicates that the workers are moving 75ft3 of dirt each hour.
The slope indicates that the entire pile of dirt will have been removed after 6 hours.
The slope indicates that the pile originally contained 450ft3 of dirt.