The shaded region in the diagram, bounded by two concentric circles, is called an annulus. The circles have radii 2cm and 14cm.
The dashed circle divides the area of this annulus into two equal areas. What is its radius?
Select one option, then click Submit.
9 \text{ cm}
10 \text{ cm}
11 \text{ cm}
12 \text{ cm}
13 \text{ cm}
Select an option, then submit.
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