Area: circumference and perimeter of semicircle

Find the area and the perimeter of the semicircle whose radius is 14 cm.

Area and circumference of a circle

The diameter of a semicircle and the base of an equilateral /_\ABC coincide in such a way that the other two sides of the triangle intersect the circumference of the semicircle at the points D and E, as shown in the diagram. If the perimeter of the triangle ABC is 6 cm, find the area of the shaded region.

The area of the circle whose circumference is equal to the perimeter of a square of side 11 cm is

Find the area of a circle whose circumference is equal to the perimeter of a square with an area of 484sq cm.

If the circumference of a circle and the perimeter of a square are equal, then

If the circumference of a circle and the perimeter of a square are equal, then