### Home > PC > Chapter 4 > Lesson 4.1.1 > Problem 4-1

4-1.

First, recall some facts that you should remember from Chapter 1.

How many radians are in a full circle?

What is the ratio of the circumference of a circle to its radius?

How many radians are in half a circle?

What are the radian measures that correspond to the following degree measures?

Review your work from problem 1-111.