如图,若反射到光电转换器接收平面上的光点从S1点移向S2点,则表明被监视的液面是 (选填“上升”或“下降”)。当液面升降高度一定时,接收平面上的光点S1和S2之间的距离与接收平面到液面的距离 。(选填“有关”或“无关”) 答案:上升 ;无关 。解析:若反射到光电转换器接收平面上的光点从S1点移向S2点,则表明被监视的液面是上升。当液面升降高度一定时,接收平面上的光点S1和S2之间的距离与接收平面到液面的距离无关。
根据图画判断句子是(√)否(×)正确。
( ) 1.
This is a movie theatre. They want to watch a movie.
( ) 2.
Let's go to the library to read a book. No. I want to buy a new dress.
( ) 3.
The weather is sunny and windy.
( ) 4.
How's the weather?The weather is cold and snowy.