If the length of the longest chord of a certain circle is 14, what is the radius of that certain circle? Choose the correct choice from the following answers.
A) 2.5	B) 5	C) 10	D) 7	E) 9

Rationale: "longest chord of a circle is the diameter of the circle diameter = 2 * radius if diameter of the circle is given as 14 = 2 * 7 so radius of the circle = 7 correct answer - d"
Answer: D