【单选题】下列所给对象能形成集合的是 --------------------- ( )
B.
方程﹙ x-1 ﹚· 2(平方)=0 的实根
【单选题】关于机械效率,下面说法正确的是: [ ]
【单选题】The world is going through the biggest wave of mergers and acquisitions never witnessed. The process sweeps from hyperactive America to Europe and reaches the emerging countries with unsurpassed might...
A.
To take in more foreign funds
C.
To combine and become bigger
D.
To trade with more countries
【单选题】关于实际使用机械时的机械效率,下列说法正确的是( )
【单选题】关于机械效率,下列说法中正确的是 [ ]
【多选题】下列关于机械效率的说法中,正确的是( )