A Sector of a Circle Is the Region Bounded by Two

A sector of a circle is the region bounded by two radii of the circle and their intercepted arc (see figure) . ​ ​
For a circle of radius r the area A of a sector of the circle with central angle θ (measured in radians) is given by A sprinkler system on a farm is set to spray water over a distance of 70 feet and rotates through an angle of 90°.Use the above given information to find the area of the region.Round your answer to two decimal places.
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A) 3,848.45
B) 1,225.00
C) 2,348.45
D) 5,348.45
E) 7,696.90