# Circles: Piece of the Pi Quiz

Think you’ve got your head wrapped around Circles? Put your knowledge to the test. Good luck — the Stickman is counting on you!
Q. A circle divides a plane into ___ regions, including the circle itself.

1
2
3
4
5
Q. In the following figure, points A, B, and C are on ⊙O. Which of the following angles are central angles of ⊙O?

AOC only
OBC only
OBC and ∠OCB only
AOC, ∠AOB, and ∠BOC only
All angles in the figure are central angles
Q. The radius of ⊙P is 3 cm. What is the exact circumference of ⊙P?

3π cm
6π cm
9π cm
1.5π cm
cm
Q. Suppose arc AB and arc CD are congruent. Which of the following is a true statement?

Arc AB and arc CD have the same measure, but they might not have the same length.
Arc AB and arc CD have the same length, but they might not have the same measure.
Arc AB and arc CD have the same length and the same measure, but they might not have the same radius.
Arc AB and arc CD have the same length, the same measure, and the same radius.
None of the above
Q. Arc ST has measure 60° and radius 6 cm. What is the exact length of arc ST?

2π cm
36π cm
2π°
36π°
360°
Q. In the figure below, points A, B, and C are on ⊙O. If m∠AOB = 30° and ∠BOC is a right angle, what is the measure of arc ABC?

30°
90°
60°
120°
240°
Q. In the figure below, points A, B, C, and D are points on ⊙O and lines AC and BD intersect at O. m∠AOB = 24°. Distance OB is 5 km. What is the exact measure of arc BC?

24°
156°
204°
km
km
Q. Suppose arc LM and arc PQ have the same length. Which of the following must be true?

Arc LM and arc PQ have the same measure.
Arc LM and arc PQ have the same radius.
Arc LM and arc PQ are congruent.
Arc LM and arc PQ are the same arc.
None of the above
Q. The circumference of ⊙O is exactly 56 m. Which of the following is closest to the radius of ⊙O?

17 m
4 m
178 m
18 m
9 m
Q. A semicircle always _____.

is a major arc
is a minor arc
is an arc with measure 180°
subtends a central angle that is acute
has an arc length equal to its arc measure