When you arrive at the lake, your friend realises he hasn’t got any swimming trunks. you need to ride to a sports shop. the sports shop is 8350 metres away. how many metres is it to cycle there and back?
The diameter of the moon is about 3500 km. approximate the surface area of the moon using the formula for the surface area of a sphere, s = 4? r^2. write your answer in scientific notation.