根据现场条件,全煤厚孔及煤体注水孔用()施工,底煤厚用()施工,但因煤层中夹矸较厚钻孔较深时,也可用岩石电钻施工。
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汽轮机单阀和顺序阀在切换过程中可以中间终止切换,恢复原运行方式。()
A. 正确
B. 错误
Which of the following data network would you implement if you wanted a wireless network that had a relatively high data rate, but was limited to very short distances?()
A. Broadband personal comm. Service (PCS)
Broadband circuit
C. Infrared
D. Spread spectrum
E. Cable
根系的水平分布范围,在正常情况下,多数与树木的()大小相一致,施肥应在树冠外围于地面的水平投影处()施肥,才有利养分充分吸收。