题干
Smoking does great harm to our health.________is smoking allowed in public places.
A：At no time
B：In no time
C：At all times
D：All the time
答案(点此获取答案解析）
A
Smoking does great harm to our health.________is smoking allowed in public places.
A：At no time
B：In no time
C：At all times
D：All the time
的解集是M, 方程
的解集是N, 3∈M且3∈N,那么
等于 ( )
