A. 4 B. 3 C. 6 D. 5
A. 200~300mm B. 10~20mm C. 20~30mm D. 700~800mm
A. 粘贴纤维布法 B. 粘贴高强钢筋法 C. 粘贴钢板法 D. 粘贴FRP筋法
A. noise and vibration B. an increase in discharge pressure C. an increase in suction pressure D. lifting of the relief valve
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