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Question:

Really Complicated Math Problem?

A 1? oz. bottle of roll-on deodorant has a height of 4 in. and a radius of ? in. Find the surface area of the bottle if the bottle is shaped like a silo. Use 3.14 for π.Altitude of a launched object. The altitude of an object, in meters, is given by the polynomialh + vt ? 4.9t^2where h is the height, in meters, at which the launch occurs, v is the initial upward speed (or velocity), in meters per second, and t is the number of seconds for which the object is airborne.

Answer:

1. It's a silo, which is a cylinder and a hemisphere. The height is 4 inches, from the bottom of the cylinder to the top of the hemisphere. So, the height of just the cylinder is 3 and a quarter inches, or 13/4 inches (Because 3/4 of it is the hemisphere). The surface area of a cylinder is denoted by 2*PI*r*L, where L is the height and r is the radius (Same radius as the hemisphere). Thus, for the cylinder part, you get 2*3.14*0.75*3.25 ~ 10.6 inches. The hemisphere is just a half of a sphere. The surface area of a sphere is 4*pi*r^2, and so the surface area of a hemisphere is 2*pi*r^2, or 2*3.14*0.75^2, or around 3.5 inches. Thus, you add the two together and you get that the silo is 14.1 inches in surface area.

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