问题
选择题
关于电流跟电压的关系下列说法中，正确的是[ ]
A．电流跟电压成正比
B．通过导体的电流跟导体两端的电压成正比
C．在电阻不变的情况下，导体中的电流跟导体两端的电压成正比
D．电阻一定时，通过导体的电流大小跟这段导体两端的电压成反比
答案
答案：C
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关于电流跟电压的关系下列说法中，正确的是[ ]
A．电流跟电压成正比
B．通过导体的电流跟导体两端的电压成正比
C．在电阻不变的情况下，导体中的电流跟导体两端的电压成正比
D．电阻一定时，通过导体的电流大小跟这段导体两端的电压成反比
答案：C
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| Mr and Mrs Smith have two sons ① one daughter. The older son is 12 ② old. ③ name is Jack. His brother Jim is four years ④ than him. Mary is Jack's twin sister. She is a pretty girl. But she is ⑤ than her two brothers. They are ⑥ in the same school. Also Mary and Jack ⑦ in the same class, Class 2, Grade 6. Their younger brother Jim is ⑧ Class l, Grade 2. The children go to school ⑨ bus every day. They ⑩ happy in their school. |
| （ ）①A. or （ ）②A. year （ ）③A. Her （ ）④A. older （ ）⑤A. thiner （ ）⑥A. both （ ）⑦A. is （ ）⑧A. on （ ）⑨A. take （ ）⑩A. feels | B. but B. years B. His B. younger B. thinner B. too B. am B. at B. bye B. feel | C. and C. year's C. Hers C. old C. thin C. all C. are C. in C. by C. felt | D. with D. a year D. Its D. young D. as thinner as D. to D. be D. of D. buy D. are feeling |