The circumference is the distance around the circle. It relates the number of times the diameter will encircle the circumference as 3.14 or π. As a result, the formulas for the circumference of a circle are C = 2πr or C = πd. The information given is the diameter so use C = πd by substituting d = 6.
It’s 9 because the whole number is eight, but seven is going to bring the number up ( five or more raise the score, four or less let it rest.) Good luck !