许多城市禁止燃放烟花爆竹。原因是燃放烟花爆竹时[ ]
①产生有害气体②产生噪音③产生粉尘④易引发火灾
A.①②③④
B.只有①③
C.只有②④
D.只有②③④
答案:A
I have no________with people who are always complaining of their misfortunes. [ ]
A. devotion
B. belief
C. patience
D. balance
十进制数45用二进制数表示是
A.1100001
B.1101001
C.0011001
D.101101