AC and BD are two perpendicular diameters of a circle ABCD. Given that the area of the shaded portion is 308 cm², calculate :

(i) the length of AC; and

(ii) the circumference of the circle.

AC and BD are two perpendicular diameters of a circle with centre O. If AC = 16 cm, calculate the area and perimeter of the shaded part.

Find the area of a circle inscribed in an equilateral triangle of side 18 cm.

The shape of the top of a table in a restaurant is that of a segment of a circle with centre O and ∠BOD = 90°. BO = OD = 60 cm. Find :

(i) the area of the top of the table;

(ii) the perimeter of the table.