检查机尾架是否平直、（）是否齐全、机尾滚筒是否牢固，有无塞煤、卡矸现象，如有应立即处理。
A.缓冲托辊
B.托辊
C.跑偏装置
D.皮带保护
参考答案：A
However, unfulfilled ______ of technology application have created a gap between earth observation services and the application markets not integrated into the economic mainstream.
A．charges
B．pledges
C．mergers
D．charts
对参加国际联运的中方铁路货车有哪些技术要求？
