Assume the Rate of Change in the Height H of a Tree

Multiple Choice

Assume the rate of change in the height h of a tree with respect to its age a is inversely proportional to the tree's height (with a proportionality constant of one) . If the tree is 23 feet tall at age 21, how tall was the tree at age 5? Round your answer to the nearest foot.

A) 2 feet
B) 3 feet
C) 10 feet
D) 22 feet
E) 21 feet