题目

如图所示，虚线a、b、c是电场中的三个等势面，相邻等势面间的电势差相同，实线为一个带正电的质点仅在电场力作用下，通过该区域的运动轨迹，P、Q是轨迹上的两点。下列说法中正确的是   （   ）A.三个等势面中，等势面a的电势最高B.带电质点一定是从P点向Q点运动C.带电质点通过P点时的加速度比通过Q点时小D.带电质点通过P点时的动能比通过Q点时小  完形填空。     "Fit for body, fit for study." is an interesting exercise program of a high school. After 4:20 p.m. allthe students of the high school    1   on the playground to run for exercise.     Every afternoon from Monday to Friday, one hour before supper the Students at school    2   the playground to run for 40 minutes. The high school started the    3   last winter Why did the school do so? When the winter came, many students were    4   to catch a cold or get sleepy during evening classes.The school was worried about it and then they    5   upwiththe exercise program to make a change.      Now most students prefer to   6   an active part in the program and benefit (受益) From it in the highschool.     It gets my brain (大脑) active and makes me learn more, so I'm ready for    7   classes, said Li Lin in Grade Three.      "I'm getting    8   now, so I don't get a cold in winter said Gao Lei in Grade Two.      But some students were not    9   inthe program at first However MID months later, the program worked well. Most students didn't get sleepy any more during evening classes-And   10   students got a cold in winter. Actually, the program suited them just fine.    Today all the students fall in love with the sport program. They run every-day to keep healthy for their bodies and studies. (     )1．A．get to     (     )2．A．come to    (     )3．A．change     (     )4．A．possible   (     )5．A．put        (     )6．A．take       (     )7．A．morning    (     )8．A．confident      (     )9．A．excited    (     )10．A．few        B．get on         B．come on         B．study            B．easy           B．came            B．regard          B．afternoon           B．strong         B．exciting        B．a few          C．get together       C．come out            C．display              C．deep              C．added                C．join                C ．evening             C．correct              C．interesting       C．a little         D．get from        D．come up              D．program           D．serious           D．realized             D．experience                       D．noon                D．warm                 D．interested       D．little