Question

Define circle
it's perimeter
radius
chord​

Define Rectangle
it's perimeter
area

Define square
it's perimeter
area.​

Answer 1

Explanation:

Circumference of the circle or perimeter of the circle is the measurement of the boundary of the circle. Whereas the area of circle defines the region occupied by it. If we open a circle and make a straight line out of it, then its length is the circumference.

Area of semi-circle: πr2/2

Area of circle: πr2

Perimeter of semi-circle: πr

Circumference of Circle: 2πr