The circle to the right has a radius of one meter.

1. How many degrees are in a half circle?

   Answer (a):

   It is half of $360°$ or $180°$.

2. What is the length of the arc that covers half of the circle?

   Hint (b):

   Since the circumference of the circle is $2\pi(\text{radius})$, the answer is $2π\left(1\right)$. So what is the arc length of half of the circle?

3. Using exact values, what is the length of $\overarc { A B }$? You will have $\pi$ as part of your answer.

   Hint (c):

   What part of the circumference will 60° have?

   Answer (c):

   $\frac{1}{6}\text{ of the circumference or }\frac{2\pi}{6}$