WHAT YOU NEED: an orange, pencil and paper. The orange should be as round as possible, so the peel represents the surface area of a sphere. STEP 2: Repeat this 3 more times. You should now have 4 ...

The surface area of the sphere is equal to 4 circles of the same radius. Surface area of a sphere. Image gallery Skip image gallery. Image caption, Click to see a step-by-step slideshow.