The distance a car travels on a flat highway is directly proportional to the quantity of gas consumed. A Ferrari travels $280$ miles on $8$ gallons of gas.

(a) What is the constant of proportionality, and what are it units?
Choose miles gallons miles per gallon help (numbers)

(b) What is the meaning of the constant of proportionality $k$?
A. A Ferrari on the highway will travel $k$ miles.
B. A Ferrari on the highway will travel $k$ miles on a gallon of gas.
C. A Ferrari on the highway will use $k$ gallons of gas.
D. A Ferrari on the highway will use $k$ gallons of gas every $280$ miles.
E. None of the above