【单选题】The woman got nothing in _______for her kindness, which made her very upset.
【简答题】在通用示波器中调节下列开关、旋钮的作用是什么? ( 1 )聚焦和辅助聚焦;( 2 ) X 轴移位;( 3 )触发方式;( 4 )触发电平;( 5 ) 触发极性;( 6 )偏转灵敏度粗调( V/div );( 7 )偏转灵敏度细调;( 8 ) 扫描速度粗调( t/div )。
【单选题】示波器实验中,示波器工作时荧光屏上的波形亮度较弱,则应调节的旋钮是( )
【简答题】Her friend's kindness has restored her faith ____human nature.
【多选题】我国现行的社会保险主要包括哪些保险项目?
【简答题】完形填空。 My 8-year-old daughter is experimenting with kindness and smiles. She has been her own colourful smile cards and 1 packs her pockets with them when we go out. She makes them very 2 . And ...
【单选题】双踪示波器测量步骤一般分为四个步骤,其中步骤顺序正确的是( )。 A、通电前将灰度、聚焦电位器和扫描速度及衰减电位器调至最左端. B、慢慢将灰度旋钮顺时针调至荧光屏上亮点可见.缓慢调节聚焦旋钮,使亮点圆而细 C、打开电源开关通电预热三至五分钟 D、进行示波器方波校正
【简答题】示波器的“聚焦”旋钮是调节示波器中____极和____极之间的电位。