Question 1081747
area is pi*r^2
72 degrees is 1/5th of the circle's area, so the entire area of the circle is 25 pi in ^2.  
That would make the radius 5 inches ANSWER
the area of the entire circle is 25 pi in^2
the area of a sector, 1/5th the area, would have an arc of 72 degrees and an area of 5 pi in ^2.