10 An equilateral triangle of side 20 cm is inscribed in a circle.
Calculate the distance of a side of the
triangle from the centre of the circle.

Read the article titled "trans-saharan migration routes to north africa and the eu: historical roots and current trends." why do tens of thousands of sub-saharan africans try to cross the mediterranean each year? how are these refugees commonly portrayed? (site 1)

Explain why the rate of urbanisation is in the way it is between developed and undeveloped countries.

What is the amount of organic matter in all living organisms in a habitat called?