The area of the shaded sector must be 144π units².
<h3>What is the area of the circle?</h3>The area of the circle is defined as the product of the pie and the square of the radius.
The area of the circle =
We know that the angle measurement of central angle QRS is less than π radians.
for r = 18 units
The area of the circle = π18² = 324π units²
The area of the half of a circle = 324π /2 = 162π units²
The area of a quarter of a circle = 324π /4 = 81π units²
so
The area of the shaded sector < 162π units²
and
The area of the shaded sector > 81π units²
Hence the answer must be 144π units²
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