Question

1. what is the relationship between the radius and circumference of a circle? a. circumference = π×radius² b. circumference = radius×π c. circumference = 2π×radius d. circumference = 3×radius 11. a central angle of a circle measures 120°. what is the measure of the arc it intercepts? a. 60° b. 360° c. 120° d. 240° 12. what is the term for a line - segment that joins a vertex of a triangle to the mid - point of the opposite side? a. tangent b. angle bisector c. median d. midpoint

Explanation:

Step1: Recall circle - circumference formula

The formula for the circumference $C$ of a circle is $C = 2\pi r$, where $r$ is the radius of the circle. This can also be written as $C=\pi\times(2r)$.

Step2: Analyze central - angle and arc - length relationship

The measure of an arc intercepted by a central angle is equal to the measure of the central angle (when the angle is measured in degrees). So if a central angle measures $130^{\circ}$, the measure of the arc it intercepts is also $130^{\circ}$.

Step3: Recall triangle - related definitions

A median of a triangle is a line - segment that joins a vertex of a triangle to the mid - point of the opposite side. A tangent is a line that touches a circle at exactly one point. An angle bisector divides an angle into two equal parts. A mid - point is the middle point of a line segment.

Answer:

1. None of the given options are correct. The correct relationship is Circumference = $2\pi\times$Radius.
2. C. $130^{\circ}$
3. C. Median