尖轨跟部轨缝，2号单开和对称道岔为（）
A.3mm
B.8mm
C.5mm
D.6mm
参考答案：D
_________ homework, most students do it every day. [ ]
A. As for
B. As to
C. As of
D. As from
TD-SCDMA系统BBU＋RRU室内覆盖组网中，R01最大能支持（）载波进行室内覆盖。
A.6
B.3
C.4
D.2
