某河平水期平均流量为120m3/s，一级评价，河流断面形状近似矩形_爱下问搜题

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问题单项选择题

某河平水期平均流量为120m³/s，一级评价，河流断面形状近似矩形，河宽45m，水深6m，在取样断面上应取( )个水样分析。

A．6
B．4
C．5
D．2

答案

参考答案：B

解析：首先判断平水期平均流量为120m³/s的河流为中河，河宽小于50m，共设两条取样垂线，水深大于5m，每个垂线取2个样，因此其取样断面上水样分析数应为2×2=4。

完形填空

When we are unfamiliar with something, we may feel nervous and fearful. The help of others is a good   36   to help us pull through.
I write for a big newspaper, and I wanted to   37   a story about parachute jumping（跳伞）. To make it a realistic as well as exciting   38   , I decided that I had to make a jump myself   39  . Unluckily, I’m not good at any   40  , let alone（更不用说）parachute jumping.
My friend Mr. Smith was willing to give me a   41   . He took me to a ground school. The first day’s   42    included several hours of instruction but not my first drop from a(n)   43 . For this, I had to wait until the following   44  .
The next morning, I was taken to the airfield.   45  , a heavy parachute was put on my back. Then I was   46    to make my way to a small plane which had just stopped slowly on the runway. Once on board, the plane was soon   47   . I began to feel nervous. As we reached one thousand meters, Harry, my teacher, hooked（钩）a   48   from my parachute to a steel ring inside the plane. The line was to pull my parachute    49  after I jumped.
“Get   50  , Henry,” Harry said. I moved carefully to the door. I wanted to   51  , “NO, no, no!” But no word came.
“Jump!” Harry called   52   . “Jump!”
Away from the plane, and down, down I fell, arms stretched. It worked All at once I was very happy. Then I felt a quick   53  . My big parachute had opened! It was the best   54   I ever had. I looked down. There were rivers, trees, fields and houses. I heard the soft sound of the air. This was   55  .

D．entertainment

C．competition

单项选择题

园林中配电箱的安装高度为中心距地（）以上。

A、0.5m

B、1.0m

C、1.5m

D、2.5m