1. A straight line segment that extends from the center to any point on the circle.
2. A straight line segment whose endpoints both lie on the circle.
3. A chord that passes through a circle's center, Its measure is twice the measure of the radius.
4. An arc with a measure equal to 180° or ½ the circumference of a unit circle.
5. A portion of the circumference of a circle with " ` " symbol.
6. An arc of a circle that measures greater than 0° but less than 180°. 2 capital letters are used to name the arc.
7. An arc of a circle that measures greater than 0° but less than 360°. Name using 3 capital letters.
8. An angle formed by two rays whose vertex is the center of the circle.
9. An angle whose vertex is on the circle and whose sides contain the chords of the circle.
