题目

以下所给数据最接近实际的是（ ）A. 一桶饮水机桶装水的质量大约1tB. 人教版九年级物理课本的厚度约为10cmC. 中学生跑完800m所用的时间是50sD. 中学生上学步行的速度约为1.1m/s 答案：【答案】D【解析】试题饮水机桶装水的体积在25L=25dm3=0.025m3左右，质量在m=ρV=1.0×103kg/m3×0.025m3=25kg左右，故A不符合实际；中学生食指的宽度在1cm左右，九年级物理课本的厚度与此差不多，在1cm左右，故B不符合实际；中学生跑完800m的时间在200s左右，故C不符合实际；D、中学生正常步行的速度在4km/h=4×1/3.完形填空,通读下面短文，掌握其大意，然后在各题所给的四个选项中选出一个最佳选项。One sunny afternoon, a seven-year-old girl went for a walk. She crossed a large area of grassland into the woods_____she realized that she was lost.Sitting on a rock and_____what to do, she began crying. After a while，she_____to walk along a path with tall trees and thick bushes. When it was getting dark, she saw a small, dark wooden house. She opened the door and_____entered. Suddenly, she heard a strange noise, and she ran out of the door and back to the______Cold and tired, she fell asleep near a stream（小溪）.The girl’s parents were out and her dog, Laddy, was at home. Laddy sensed that his mistress（女主人）was in danger. He jumped_____a window, breaking the glass. He looked in the fields. But he couldn’t find his mistress anywhere. However, from the ground came a_____scent (气味) as he lowered his head. He_____the scent and walked across the grassland. Barking_____into the air, the dog____through the woods until he found the______But the girl was not there, so he headed back to the woods. Much to his delight, he saw his mistress’ blue shirt in the distance. He_____over some bushes and saw the little stream, where the girl was_____When she opened her eyes and_____her dog standing beside her, the girl said, “you_____me, Laddy,” and she kissed him several times. Seeing their daughter and dog coming back, the parents were happy. That night Laddy had a hero’s supper: a huge meal of pork.【1】A. before B. since C. while D. as【2】A. wondering B. forgetting C. remembering D. repeating【3】A. preferred B. refused C. failed D. decided【4】A. carelessly B. carefully C. hopelessly D. unwillingly【5】A. trees B. bushes C. woods D. grasses【6】A. at B. through C. in D. onto【7】A. terrible B. strange C. pleasant D. familiar【8】A. missed B. discovered C. followed D. noticed【9】A. calmly B. loudly C. happily D. gently【10】A. searched B. found C. looked D. travelled【11】A. window B. girl C. house D. hero【12】A. jumped B. climbed C. walked D. flew【13】A. awake B. afraid C. available D. asleep【14】A. listened B. watched C. heard D. saw【15】A. disturbed B. comforted C. saved D. scared