I have two faces, two planes of the same size, both round; There's another side. I am the same thickness from top to bottom. Do you know who I am? Yes, I am a cylinder. I have other characteristics. Cut me along a high line, the side is rectangular, the length is equal to the circumference of my ass and the width is equal to my height; Sometimes singing is equal to the height and the width is equal to the circumference of the bottom. So my horizontal area is the perimeter of the bottom multiplied by the height. Now, I believe you will remember my surface area. Yes, my surface area is equal to the side area plus two land areas. Be careful when calculating. First, get the perimeter of the bottom surface and multiply it by the high lateral area. This is the first step, the second step is to get the bottom area, and the third step is to add lateral area and two land areas. Although my surface area is very troublesome to find, my volume is relatively simple to find. Because I, like cuboids and cubes, are objects with uniform thickness, my volume formula is also the bottom area multiplied by the height.

Distinguish between my surface sum and volume formula, and distinguish it when applying it, otherwise you will make mistakes.

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