An arc of length 121 cm makes an angle 77° at the centre of a circle. The radius of the circle is

The radius of a circle is 14 cm and the area of a sector is 102.7 sq. cm. The central angle of the sector is

The area of a circle is 40π² . The area of a square with sides equal to radius of the circle is

The length of a rectangle is 1 cm more than its width and its perimeter is 14 cm, then the area of the rectangle is

If the radius of the circle is increased by 100%, then the area is increased by

Two equal arcs of different circles C1 and C2 subtend angles of 60° and 75° respectively, at the centres. What is the ratio of the radius of C1 to the radius of C2?