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\begin{aligned} &=\pi\left\{(6 \mathrm{~m})^{2}(7 \mathrm{~m} / \mathrm{s})+(5 \mathrm{~m}) 2(6 \mathrm{~m})(3 \mathrm{~m} / \mathrm{s})\right\} \\ &=\pi\left\{252 \mathrm{~m}^{3} / \mathrm{s}+180 \mathrm{~m}^{3} / \mathrm{s}\right\} \\ &=432 \pi \mathrm{m}^{3} / \mathrm{s} \approx 1357.2 \mathrm{~m}^{3} / \mathrm{s} \end{aligned}