Aspruce tree was measured three years after sprouting at a height of 3.87 feet. after its sixth year, the tree reached a height of 7.74 feet. assuming a constant rate of growth, which of the following statements applies? a. an additional 3.87 years is associated with an additional foot of growth. b. an additional year is associated with an additional 3.87 feet of growth. c. an additional 1.29 years is associated with an additional foot of growth. d. an additional year is associated with an additional 1.29 feet of growth.