1. An instrument used to draw circles.
2. The shape of a circle.
4. The ratio of the circumference and diameter of any circle.
6. The number of square units occupied by the space inside the circle.
8. A part of a circle named by its endpoints.
10. A location in space that has no thickness.
11. The distance from the center of a circle to any point on the circle.
12. The distance around a circle.

1. A line joining two points on the circle.
3. The distance across a circle through its center.
4. A circle divides a __________ into three parts.
5. Plural for half a diameter.
7. A circle has 360 of these units.
9. A shape with all points the same distance from its center.
13. All points in a circle are the same distance from this point.