WTZJ-II型CIR送受话器接线排XS3中白色的线是()。
A、EARIN
B、I
C、II
D、HOOK2
参考答案:B
This is an unpleasant subject_ ____ we might argue for a long while. [ ]
A. in which
B with them
C. about which
D with it
图示结构中,杆CD的轴力大小Ncd是:()
A.拉力
B.零
C.压力
D.不定,取决于P1与P2的比值