题干
Once the poison is________，there is no further danger.
A：brought up
B：brought in
C：brought back
D：brought about
答案(点此获取答案解析）
A
Once the poison is________，there is no further danger.
A：brought up
B：brought in
C：brought back
D：brought about
2CuO+4NO2↑+O2↑+6H2O↑，若将生成气体收集后，冷却至室温使其充分反应，所得溶液溶质的质量分数为