math
A stack of 10 quarters is a cylinder. If the diameter of a single quarter is 2.2 cm and the approximate height is 0.17 cm, what is the surface area of a 10-quarter stack?
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The surface area of a 10-quarter stack can be calculated by first finding the radius of the stack. The radius is equal to the diameter of one quarter divided by two, or 1.1 cm. The surface area is equal to the area of the base of the cylinder (π•r2) plus the area of the top (π•r2) plus the area of the lateral surface (2•π•rh). Therefore, the surface area of a 10-quarter stack is equal to 4•π•(1.1 cm)2 + (2•π•1.1 cm•0.17 cm) = 11.2 cm2.
