Answer: The black will filled by (1) -0.04, (2) 1 , (3)-0.04 and (4) Change in the fuel remaining in each mile.
Step-by-step explanation:
From the given table we can noticed that the fuel remaining (gallons) decreases as distance (miles).
It is clear that the distance increases by 1 mile for each next row and the remaining fuel is changed for each next row is,

The change in fuel remaining from one row to the next in the table is -0.04 gallons.
The change in distance from one row to the next in the table is 1 mile.
The slope is the rate of change of remaining fuel with respect to change in distance.

The slope of the line that runs through the points given in the table is -0.04.
The slope indicates a Change in the fuel remaining in each mile. The slope is -0.04 it means the remaining fuel decreases by 0.04 gallons in each mile.