Find the area of the shaded region. Express your answer in terms of π . A shaded rectangle with three unshaded circles stacked one above the other inside the rectangle. The horizontal length of the rectangle is 18 inches. On the right side of the rectangle, the length of the vertical side is subdivied into 4 different lengths using arrows. The first arrow indicates that the distance from the top of the rectangle to the top of the first circle is 3 inches. The second arrow indicates that the distance from the top to the bottom of the first circle is 6 inches. The third arrow indicates that the distance from the top to the bottom of the second circle is 9 inches. The fourth arrow indicates that the distance between the top to the bottom of the third circle is 12 inches.