### Home > PC > Chapter 1 > Lesson 1.2.2 > Problem 1-88

1-88.

What part of the circumference is the arc *AB*?

How do you know?

What is the formula of the circumference of a circle?

Circumference = 2π(radius)

1-88.

What part of the circumference is the arc *AB*?

How do you know?

What is the formula of the circumference of a circle?

Circumference = 2π(radius)