中国已经承诺，到2020年将单位经济产出的二氧化碳排放削减40%至45%，但到目前为止一直要求发达国家资助其实现这一目标。

China has committed to cut its emissions per unit of GDP by 40-45 per cent by 2020 but had hitherto demanded financing from the developed world to help it achieve this.

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通常情况下，同猪和牛相比，每单位体重或增加每单位体重，昆虫产生更少的甲烷、一氧化氮和氨气。

The insects generally produced less methane, nitrous oxide and ammonia both per unit of body mass and per unit of mass gained than pigs or cattle.

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碳排放税将为每单位二氧化碳设置一个具体的成本，并因此为碳确定一个清晰的成本。

A carbon tax would set a specific cost per unit of carbon dioxide, thus establishing a clear cost for carbon.

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