摘心是一二年生花卉的栽培措施之一,但下列()花卉不能摘心。
A.一串红、孔雀草、百日草
B.毛地黄、蜀葵、鸡冠花
C.矮牵牛、长春花、桂竹香
D.金盏菊、翠菊、硫磺菊
参考答案:B
根据右图回答,下列说法不正确的是:
A.此装置用于电镀铜时,电解一段时间,硫酸铜溶液的浓度不变
B.燃料电池中正极反应为O2+4e-+4H+=2H2O
C.若a为粗铜,b为纯铜,该装置可用于粗铜的精炼
D.电子经导线流入a电极
Whitney Houston’s sudden death suggests that drug abuse is such a serious problem ___we should deal with properly.
A.as
B.that
C.which
D.where