2
The distance all the way around the circle.
4
A line that goes from one edge of the circle to another and passes through the center of the circle.
5
A line that goes from the center of the circle to the edge of the circle
6
A line that crosses through the circle at two points.
7
A line that touches the circle at only one point.
8
A line that goes from one edge of the circle to another and does NOT pass through the center.
9
An arc that measures more than 180 degrees.
10
An arc that measures less than 180 degrees
12
The ratio of a circle's circumference to its diameter. Also 3.14159265359
