问题
单项选择题
圆管流动过流断面上切应力分布为( )。
A．在过流断面上是常数
B．管轴处是零，且与半径成正比
C．管壁处是零，向管轴线性增大
D．按抛物线分布
答案
参考答案：B
搜题请搜索小程序“爱下问搜题”
圆管流动过流断面上切应力分布为( )。
A．在过流断面上是常数
B．管轴处是零，且与半径成正比
C．管壁处是零，向管轴线性增大
D．按抛物线分布
参考答案：B
完形填空（15小题，共30分） 阅读下面短文，掌握其大意，从每题所给的A、B、C、D四个选项中，选出最佳选项并在答题卡上将该项涂黑。 More good things come from small things About a year ago, a couple with three children moved into the apartment next door to me. I never heard any 36 from the children, but the parents were always shouting at the kids. We 37 often in the hallways when we were coming or going. I 38 spoke, but the only 39 I ever got was a hello from the four – year – old girl. I usually go out for breakfast and one day when I 40 they were just coming from their apartment and the little girl was holding the door 41 for the others. I 42 in the car doing unnecessary things because I didn’t like to be snubbed（冷落）. The parents were 43 her to hurry and get in the car, I looked up and saw the little girl was 44 holding the door open, 45 for me. I hurried as much as I could and 46 her. She was smiling from ear to ear. That afternoon I saw a white toy bear, I 47 the little  girl and said to myself, “I 48 she would like that” so I bou ght it. I wrote a note 49 how much her act of kindness had touched a soft spot in an old man’s 50 .The next day there  was a 51 on the door and 52 was the little girl and her father. She was so proud of her bear and thanked me. Then I 53 her mother and the other children were there in the hall too. The mother and father both thanked me.Now when we meet in the hall we all speak, and in a 54 manner, I might add. 55 time passes, I don’t hear that shouting as often. In fact, hardly at all.
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