Mark starts a rock climb when he is 1 mile above sea level. He can climb at the rate of 1.5 miles per hour. Which of the following functions would express Mark's height above sea level over time?
A. f( x) = 1.5 x
B. f( x) = 2.5 x
C. f( x) = 1 + 1.5 x
Its C because you start out at 1 mile above sea level, then each time Mark climbs he goes up 1.5 miles per hour. f(x)= 1(starting point) + 1.15x (miles per hour).