The diameter PQ has divided the circle into two equal parts which are called . 

All diameters of circles are chords

All chords of a circles are its diameter.

The length of the diameter of a circle is twice the length of its radius.

Sector of a circle is the part of a circular area.

Arc of a circle is the part of a circle.

Center of a circle is a fixed point in a circle.

Two diameters of a Circle always intersects each other.

With the help of a compass and a pencil a $3 \mathrm{cm}$ circle is drawn. Let's name its center, radius, diameter, chord, arc.