Suppose You Are at the Base of a Hill, and You

Suppose you are at the base of a hill, and you see a sign that reads "Elevation 4000 feet." The road you are on goes straight up the hill to the top, where you see another sign that reads "Elevation 4500 feet." If the top of the hill is 5 horizontal miles from the base, what is the growth rate in your elevation with respect to horizontal distance as you drive up the road?

A) 150 feet per mile
B) 100 feet per mile
C) 200 feet per mile
D) 500 feet per mile