A circle has a radius of $10$ cm.

1. Find the circumference and area of the circle using exact values.

   Hint (a):

   $\text{circumference} = \left(2\right)\left(π\right)\left(\text{radius}\right)$

   $\text{area} = π\left(\text{radius}\right)^{2}$

2. Find the area and arc length of the non-shaded portion.

   Hint (b):

   What part of the circumference and area is needed?