Find the sum of all interior angles of the following regular polygons.

Hexagon

Find the sum of all interior angles of the regular Nonagon.

Find the sum of all interior angles of the regular polygon of $11$ sides.

Find the sum of all interior angles of the regular polygon of $16$sides.

What is the number of sides of a regular polygon having the sum of angles as $1980°$?

What is the number of sides of a regular polygon having the sum of angles as $3240°$?

Find the measure of each exterior angle of a regular hexagon.

If the measure of each exterior angle of a regular octagon is $k°$, then find the value of $k$.

Find the measure of each exterior angle of the following regular polygon.

Nonagon