A sector of an angle `90^(@)` is called.

Make a sector of angle 90^(@) in a circle of radius 3.5 cm.

A sector containing an angle of 90^(@) is cut from a circle of radius 42 cm and folded into a cone. Then, the curved surface area of cone is

Find the difference of the area of a sector of angle 90^@ and its coresponding major sector of a circle of radius 9.8 cm

An angle measuring 90^(@) is called

The angle of a sector of a circle is 90^(@) . The ratio of the area of the sector and that of the circle is ______.

A sector has a central angle of 270^(@) and a radius of 2. What is the area of the sector?