**Circle O has radius r. If an arc of the circle has a length of r/2, what is the measure of the central angle subtended by the arc?**

1 radian

π radians

π/2 radians

1/2 radian

**Answer:**

**Circle O has radius r. If an arc of the circle has a length of r/2, what is the measure of the central angle subtended by the arc?**

1 radian

π radians

π/2 radians

1/2 radian

**Answer:**