1. (a) Sketch a diagram of a pentagon.
(b) Calculate the sum of the exterior angles.
(c) Calculate the sum of the interior angles.
(d) If the pentagon were regular, what would be the size of each:
(i) Exterior angle (ii) Interior angle
2. The diagram shows a regular sevensided polygon (a heptagon).
(a) What is the sum of the exterior angles? (b) Calculate the sum of the interior angles. (c) What is the size of each: (i) Exterior angle? (ii) Interior angle? 
3. Find the sizes of the angles marked by letters.
(a) 
(c) 
(b) 
(d)

4. The interior angle of a regular, n − sided polygon =
(a) Find the size of an interior angle of:
(i) a square
(ii) an regular octagon
(iii) a regular dodecagon (12 sides)
(iv) an regular icosagon (20 sides)
(b) What do the answers to part (a) show about the relationship between the number of sides of a regular polygon and the size of each interior angle?
5. The exterior angles of a regular polygon are each 18°.
How many sides has the polygon?
6. The interior angles of a polygon add up to 1800°.
How many sides has the polygon?