When a certain tree was first planted, it was 4 feet tall, and 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 1/4 taller than it was at the end of the 4th year. By how many feet did the height of the tree increase each year?  Choices.
A) 1	B) 2/5	C) 1/2	D) 2/3	E) 6/5
Say, the tree grows by x feet every year.   Then, 4 + 6x = (1+1/4)(4+4x)   or, x = 1   1nswer 1
<result>A</result>
When a certain tree was first planted, it was 4 feet tall, and 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 1/4 taller than it was at the end of the 4th year. By how many feet did the height of the tree increase each year?