Wind Speed Varies in the First Twenty Meters Above the Ground

Multiple Choice

Wind speed varies in the first twenty meters above the ground. For a particular day, let $f ( x ) = 9.8 \ln x + 3.3$ model the wind speed $x$ meters above the ground. At what height is the wind speed 9 meters per second? Round results to the nearest hundredth.

A) 1.79 m
B) 0.58 m
C) 0.49 m
D) 0.56 m