The chord of a circle can be defined as the line segment joining any two points on the circumference of the circle.

Diameter is the longest chord of a circle which passes through centre joining the two points on the circumference of a circle.

Use the area to find the radius:

Area = 100π cm²

100π = πr²

Get rid of π by dividing both sides by π

100 = r²

Express 10 as a square: 100 = 10²

10² = r²

Since the powers are equal, the bases must be equal: 10 = r

Therefore, the radius is 10 cm.

Substitute the radius into the circumference formula:

Circumference = 2 x π x 10 cm

Circumference = 20π cm