Outside of the technical issues, there is a concern about turning foodâcorn in the U.S.âinto fuel. Partially driven by an 8-percent rise in corn orders from ethanol plants, corn prices doubled in the last six months of 2010 and are expected to continue rising. There are benefits to ethanol, of course. It has a higher octane rating, so it supports a higher compression ratio and more aggressive ignition timing. Like its cousin methanol, with its high octane and clean burn, ethanol makes a good racing fuel. NASCAR, a politically astute organization, is running E85 this season.
I agree with Diane that with this meaning of the word cylinder it has 3 faces, 2 edges and no vertices. There is however a technical meaning of the word cylinder that results in a different answer.
When a vertical strip is rotated about the y-axis it generates a cylindrical shell of thickness Îx and volume Î´V. This cylindrical shell is the difference between an outer cylinder of radius x + Îx and an inner cylinder of radius Îx. Both cylinders have height infinitely close to f(x). Thus compared to Îx,