The diagram shows a piece of wire bent to form the

The diagram shows a piece of wire bent to form the perimeter OABCO of a sector of a circle with center O and radius r cm, where angle A OC is theta radians. The wire is of length 100 cm while r and theta may vary. B C r cm O r cm AFind: a. the value of r for which the area enclosed by the wire is a maximum, b. the corresponding value of the angle AOC in degrees.