Answer:
7π cm² ≈ 22.0 cm²
Explanation:
The shaded area is the difference between the area of Circle B and the areas of Circle C and Circle O. That is, those white areas are subtracted from the area of Circle B to get the shaded area.
The formula for the area of a circle is
A = πr²
Using this, we find ...
Circle B area = π(3 cm)² = 9π cm²
Circle C area = Circle O area = π(1 cm)² = π cm²
Then the shaded area is ...
Shaded Area = Circle B area - Circle C area - Circle O area
= (9π cm²) - (π cm²) - (π cm²)
= 7π cm² ≈ 22 cm²