题目

某批产品成箱包装,每箱5件.一用户在购进该批产品前先取出3箱,再从每箱中任意抽取2件产品进行检验.设取出的第一、二、三箱中分别有0件、1件、2件二等品,其余为一等品. (Ⅰ)用ξ表示抽检的6件产品中二等品的件数,求ξ的分布列 (Ⅱ)若抽检的6件产品中有2件或2件以上二等品,用户就拒绝购买这批产品,求这批产品级用户拒绝的概率. This kind of cloth ________ well.I think it is worthy ________. [  ] A.washes; buying B.is washed; buying C.washes; to be bought D.is washed; to be bought
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