Answer:
c. 144π units²
Step-by-step explanation:
In the picture attached, the circle is shown.
Data
Area of the circle = π*r² = π*18² = 324π square units
The area of the circle is proportional to angle 2π radians. Therefore:
324π square units / shaded area = 2π radians / (8π/9 radians)
shaded area = (8π/9)/(2π)*324π
shaded area = (4/9)*324π
shaded area = 144π square units
