1Define a circle, and explain why that one definition produces every other word in this unit.
2What is the difference between a sector and a segment?
3Explain what pi is, and why it is the same number for every circle.
4A wheel of diameter 70 cm rolls along a road. How far does it travel in 100 turns, and why?
5Describe how to find the centre of a circular lid using only a ruler and a compass.