问题
单项选择题
某供电部门将配电线路导线由LGJ-25更换为LGJ-35。在输送负荷不变的条件下，忽略更换前后线路电抗值的变化，简化计算换线后降低功率损耗（）（LGJ-25导线电阻R1=1．38Ω／km，LGJ-35导线电阻R2=0．85Ω／km）。
A.60.8％
B.50.6％
C.45.3％
D.38.4％
答案
参考答案：D
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某供电部门将配电线路导线由LGJ-25更换为LGJ-35。在输送负荷不变的条件下，忽略更换前后线路电抗值的变化，简化计算换线后降低功率损耗（）（LGJ-25导线电阻R1=1．38Ω／km，LGJ-35导线电阻R2=0．85Ω／km）。
A.60.8％
B.50.6％
C.45.3％
D.38.4％
参考答案：D
| 阅读理解。 | |||
| We see many animals, like rabbits, bees, birds, sheep and so on, but do you know 1 these animals say things? First, let’s see a rabbit. When a rabbit sees something 2 , it runs away at once. When it runs, its tail moves up and 3 . When other rabbits see this, they run 4 . Many other animals use this kind of 5 . When a bee has found some food, it goes back to its home. It cannot tell 6 bees where the food is by speaking to them, but it does a little dance in the air. They may tell other bees 7 the food is. Some animals say things by making sounds like a man does. 8 , a dog barks when a stranger comes near. Some birds can make some 9 sounds, each with its own meaning. In a word, every animal has its 10 language. | |||
| ( )1. A. how ( )2. A. interesting ( )3. A. up ( )4. A. quickly ( )5. A. way ( )6. A. the other ( )7. A. where ( )8. A. For example ( )9. A. strange ( )10.A. real | B. when B. dangerous B. again B. away B. moving B. small B. how B. Very often B. interesting B. own | C. why C. interested C. down C. too C. language C. all the C. what C. As usual C. useful C. easy | D. where D. danger D. on D. back D. running D. many D. whose D. At first D. different D. old |