Practice problems of the annulus

An annulus is a planar structure bounded by two concentric circles with different radii r1 and r2. It is a set of points whose distance from the common center S is between r1 and r2 inclusive. The area of the circle is the difference in the areas of the larger circle with radius r2 and the smaller circle with radius r1. In other words, an annulus is the intersection of circles with a common center and different radii.

Direction: Solve each problem carefully and show your solution in each item.

Number of problems found: 46


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