How many combinations of codons are there if there's three bases and four possibilities at each base?

那密码子的组合方式到底有几种呢,三个位点,每个位点四种选择

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As you may know, there's yet another organization where we could group this in units of four but for all intents and purposes-- there are a few nuances to it-- four is simply a multiplication of two.

也许你知道的,还有另外一种组织方式,我们可以四拍一组,但是不论出于什么动机或者目的,这其中的区别甚微,四拍就是两拍的简单相乘

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