All of the 24 Happy Meal choices have more than a third of a child's recommended daily calorie intake.

VOA: standard.2010.06.24

If I have three, I have 16 x 4 or 64 possible choices, way more than enough.

那如果是三个碱基一组,那就有16x4种,六十四种组合,那就足够了

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