扦插时,保留有芽和幼叶的插枝比较容易生根成活,这是因为芽和幼叶可以() A.迅速生长 发布时间:2018-11-26 15:54 │ 来源:www.tikuol.com 题型:单项选择题 问题: 扦插时,保留有芽和幼叶的插枝比较容易生根成活,这是因为芽和幼叶可以()A.迅速生长B.进行光合作用C.产生生长素D.表明插枝的死活
题型:单项选择题 The atmosphere in a tank is too lean if it is().A.incapable of supporting combustion because the hydrocarbon content is below the LFL (Lower Flammable Limit)B.capable of supporting combustion because the hydrocarbon content is above the UFL (Upper Flammable Limit)C.capable of supporting a fire once startedD.not safe for ballasting 查看答案