the mean free path of a molecule of diameter 5 x 10^-10 m at the temperature 41°c and pressure 1.38 x 10^5 pa, is given as ____ m. (given k_b = 1.38 x 10^-23 j/k).
// 右侧第一个 <= cur 的元素, 所以用大于的就弹出
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Екатерина Грищенко (старший редактор отдела «Бывший СССР»)
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