联锁设备的作用是什么？
参考答案：
联锁设备用于保证站内行车与调车工作的安全，并提高车站的通过能力。
that Marie was able to set up new branches elsewhere. [ ]
A. So successful her business was
B. So was her successful business
C. So her business was successful
D. So successful was her business
埋弧自动焊时，对焊接区域所采取的保护方法是（）。
A.混合气保护
B.气保护
C.渣保护
D.气—渣联合保护
