袋中有50个乒乓球，其中20个黄的，30个白的，现在两个人不放回地依次从袋中随机各取一球。则第二人取到黄球的概率是

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【单选题】【消耗次数：1】

① 1/5

② 2/5

③ 3/5

④ 4/5

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