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=2 \pi(6 \mathrm{~m})(7 \mathrm{~m} / \mathrm{s})+2 \pi(3 \mathrm{~m} / \mathrm{s})(5 \mathrm{~m})+2 \pi(2 \cdot 6 \mathrm{~m})(3 \mathrm{~m} / \mathrm{s})=186 \pi \mathrm{m}^{2} / \mathrm{s}