Use π = 3.1 and give answers to 3 significant figures.
1. Find the volume and surface area of the following sphere, if r = 8 mm.
2. A sphere has a diameter 24.2 cm . What is its volume and surface area?
3. 
For the following solid sphere, find: a. The volume. Give the answers in mm^{3} b. The surface area. Give the answers in m^{2}

4. Assuming the Earth is a sphere, with a diameter of 12,700 kilometres, find its approximate surface area. 