For multiple readers
Before we dive into the math, could you let me know which grade you're in? Also, when you hear the term "mean free path," what do you think it depends on? For example, if you imagine molecules in a gas, what physical factors would make it harder for a molecule to travel a long distance without hitting something?，更多细节参见哔哩哔哩
，详情可参考搜狗输入法
Российское посольство заявило о спекуляции молдавских СМИ20:43，更多细节参见PDF资料
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Фото: Iranian Foreign Media Department / Reuters