【单选题】如图为某收音机的变频级,以下正确叙述是 ( )
【简答题】定常流动的流体所具有的机械能有 , , 。
【单选题】The data accumulated was obtained through______
A.
observation by social psychologists
B.
conversations with mothers of the children
C.
interviews, school records and physicians' reports
D.
observation of fathers with their children
【单选题】关于新嘉年华IMRC(长短进气道控制)和IMSC(进气涡流翼板控制),下列说法有误的是?()
A.
IMRC和IMSC的阀门的打开或关闭是利用直流电机直接控制的
B.
IMRC阀板的开启时刻只与发动机的转速有关而与发动机的负荷无关
C.
IMSC阀板的开启时刻既与发动机的转速有关又与发动机的负荷无关
D.
IMRC和IMSC阀板的位置只有全开和全关两个位置而没有中间位置
【单选题】Children are sensitive to disapproval and adjust their behaviour______.
【单选题】某大型城市综合体中的变配电间、计算机主机房、通讯设备间等场所内设置了组合分配式七氟丙烷气体灭火系统。下列关于该系统组件的说法中,错误的是()。
B.
选择阀的公称直径应和与其对应的防护区灭火系统的主管道的公称直径相同
【单选题】More than 50,000 electronics retailers and distributors are expected at the McCormick Convention Center in Chicago starting next Saturday. Some 1,300 manufacturers from more than 35 countries will exh...
A.
The McCormick Convention Center
B.
Chicago's convention centers
D.
The Summer Consumer Electronics Show
【单选题】如图为某收音机的变频级,以下正确叙述是( )。【图片】