Question

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• B£® $\frac{£¨{m}_{1}+{m}_{2}£©{¦Ñ}_{1}{¦Ñ}_{2}}{{m}_{1}{¦Ñ}_{2}+{m}_{2}{¦Ñ}_{1}}$
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• D£® $\frac{{m}_{1}{¦Ñ}_{2}+{m}_{2}{¦Ñ}_{1}}{£¨{m}_{1}+{m}_{2}£©{¦Ñ}_{1}{¦Ñ}_{2}}$

Answer 1

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