通过合理地计划产品品种的生产，可以获得更多的利润，降低单位成本。

By optimizing producing plan according to system quality level, one can get more benefit and reduce unit cost.

youdao

建筑材料，是很常见的获得批量采购的折扣，所以购买的单位成本下降，从量的增加。

For construction materials, it is common to receive discounts for bulk purchases, so the unit purchase cost declines as quantity increases.

youdao

I bought a number of two-period bonds such that the value of my purchase exactly equals the proceeds that I get from shorting the one period bond, so I've made a zero wealth transaction.

我买入了一定数量的两年期债券,其成本刚好等于我卖空,一单位一年期债券获得的资金,我做的是零成本交易

耶鲁公开课 - 金融市场课程节选