电机车接近()时,都必须减速,并发出警号
A、道岔
B、弯道、巷道口
C、坡度及噪声较大地段
D、前有车辆或视线受阻
参考答案:A, B, C, D
— Who was on duty last Friday?
— . [ ]
A. I am
B. I was
C. Yes, I was
D. No, I wasn't
以下哪些是国际电联确认的3G标准()
A.CDMA2000
B.TD-SCDMA
C.WinMAX
D.WCDMA