汽机负荷过低时会引起排汽温度升高的原因是（）。A、真空过高 B、进汽温度过高 C、摩

《诗经》中风、雅、颂三个部分是根据（）划分的。

C

Stepping into a pool of water is common enough ,but who could ever imagine stopping into a pool of fish ?In February of 1974, Bill Tapp ,an Australian farmer ,saw a rain of fish that covered his farm . How surprised he must have been when he heard many fish hitting against his roof!

What caused this strange occurrence ?This is a question that had long puzzled people who study fish .The answer turned out to be a combination of wind and storm.

When it is spring in the northern part of the world ,it is fall in Australia, Throughout the autumn season ,terrible storms arise and rains flood the land .The strong winds sweep over Australia like huge vacuum（真空） cleaners, collecting seaweed ,pieces of wood , and even schools of fish .

The second thing，a dictionary will tell you the pronunciation．Most dictionaries give phonetic(语音的)，or sound alphabet(音标)．The phonetic alphabet shows pronunciation．The third thing，a dictionary will tell you the meaning of words．You can look up a word and find out what it means．Many words have more than one meaning，and a good dictionary will tell you au of the word's meanings．For example，in English the common word“get”has over 20 different meanings．

49．Many words have_____________ ．  

A．several meanings    B．one meaning    C．few meanings  D．no meaning

50．A good dictionary will tell you____________．

A．more of word's pronunciation      B．more of the word's meanings

C．more of grammar                 D．more of the word's spelling．

51．Phonetic alphabets are used to show       ．

A．handwritings   B．spelling    C．meanings  D．pronunciation

52．How many important things will most dictionaries tell you?

A．Four    B．Five    C．Three   D．Two

计算题：某给水管道炉，已知其在直径d1＝200mm处断面的平均流速c1＝0.795m/s，求在d2＝100mm处断面的平均流速c2是多少？

下列关于借记卡对账单打印的说法，正确的是（）。

A.借记卡对账单打印可在全国任意营业机构办理

B.借记卡对账单打印须持卡人本人办理

C.“打印借记卡综合对账单”或“打印借记卡明细对账单”的交易代码分别为3081和3080

D.对账单应加盖业务专用章

渗透出水流量观测方法不包括（）。

A.容积法

B.量水堰法

C.测流速法

D.垂线流速法