From this you can calculate the total mass in the Galaxy.

据此，你可以计算出银河系的总质量。

《柯林斯英汉双解大词典》

And you will get the total mass by summing these things.

对这些求总和你会得到总质量。

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Then I have the total mass of A divided by the number of moles of A.

然后是A的总质量,除以A的摩尔数。

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Eighty billion dollars of that total was to be pumped into the U.S.economy to promote development of renewable energy, urban mass transit, high-speed rail systems and clean energy jobs.

VOA: standard.2010.02.25

Even more fascinating, the supermassive black hole is about 14% of the total mass of the galaxy.

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Once the ice is fully afloat its effective contribution to the total mass of the ocean has been made.

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Curiosity carries 10 science instruments with a total mass 15 times as large as the science payloads on NASA's Mars rovers Spirit and Opportunity.

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