Answer:
Miles
Explanation:
Required
Fill in the gap
From the question, we have that
mpg = Miles per gallon
Suppose a truck has 5 mpg;
This implies that the truck can travel 5 miles using 1 gallon
What if it's 4 mpg?
This implies that the truck can travel 4 miles using 1 gallon
What if it's x mpg?
This implies that the truck can travel x miles using 1 gallon
So, basically mpg represents the number of miles a truck can go for every unit of gallon