“一花独放不是春,百花齐放春满园。”说明的道理是[ ]
A.只有有了竞争才会有合作
B.竞争对手是相互排斥的
C.竞争和合作是相互依存的两个方面
D.竞争的目的在于展现自我
答案:C
Passengers on board aren't allowed _____ calls during take-off.
A.making or receiving
B.to make or receive
C.to have made or received
D.having made or received
蒸汽式溴化锂冷水机组为保证供气压力稳定,蒸汽表压高于()MPA、时,应在机组的蒸汽调节阀与过滤器之间安装减压阀。
A、0.5
B、0.6
C、0.7
D、0.8