Answer:
Option D is the correct answer.
Step-by-step explanation:
Initial height = 4 feet
Given that the height of the tree increased by a constant amount each year for the next 6 years. At the end of the 6th year, the tree was 1/5th taller than it was at the end of the 4th year.
Let the rate of growing each year be g.
After 6 years height of tree = 4 + 6g
After 4 years height of tree = 4 + 4g
At the end of the 6th year, the tree was 1/5th taller than it was at the end of the 4th year.
That is
Option D is the correct answer.