It is the amount of electric charge per unit volume.
是电荷与体积的比值。
The Transpacific Stabilization Agreement bunker charge, a benchmark fuel surcharge imposed by shipping firms on sea freight, has risen from $455 per 40-foot equivalent unit in January 2007 to $1,130.
泛太平洋运价稳定协议组织的燃油附加费，一项船运公司在海上货物运输方面所使用的基准燃料额外收费，其每40英尺集装箱所相当的货物单位的费用已经从2007年1月的455美元上涨到1130美元。
The current is the charge flow per unit time .
电流是每单位时间流动的电荷。
The claim is that the telecoms companies charge us more per unit of data to send a text message next door than it costs to send a message to Mars.
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Because the number of potential customers for such experimental sensors is small, the firms manufacturing them have to charge a high price per unit just to cover the fixed costs of designing the product, setting up the factory, and so forth.
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The way it might work is that the typical replicator will have patterns stored for common things, but the owners of something really special like Bass Ale will figure out a way to encrypt the structure so that they can charge you on a per unit basis.
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