780A设备加载扩展子框时，扩展框上的REG盘的开关K2应拨号为（）？
A.8
B.12
C.10
D.4
参考答案：C
I have bought two ballpens, ____ writes well. [ ]
A. none of them
B. neither of them
C. neither of which
D. none of which
如果等腰三角形的周长为12cm，一边长为5cm，那么它的腰长为______cm．
