搜题请搜索小程序“爱下问搜题”
问题 选择题

Only after my friend came ____.[ ]

A. did the computer repair      

B. he repaired the computer        

C. was the computer repaired    

D. the computer was repaired

答案

答案：C

完形填空

Wanted
FAIRMONT HOTEL
Five Waiters and Ten Waitresses:
—Aged under 22.
—At least high school graduates.
Good-looking men at least 1.72 meters tall and women at least 1.65 meters tall.
—Paid 1.600-2,200 dollars per month.
One Secretary:
—Aged under 30.
—Females（女性） only.
—Good at writing and skilled at computer.
—Paid 2,000-3,000 dollars per month.
If you are interested, call 465-4768.
Fax: 6954828
WILSON BOOKSTORE
Accountant(会计):
Aged between 25 and 40.
—With an experience of at least two years.
With a degree and an accountant certificate(证书).
—Paid 3,000-4,000 dollars monthly.
—With a practical knowledge of computer.
Computer Salesclerk:
—Aged 25 or less.
—Basic education of 12 years or more. Good at computer.
Paid 1,800-2,200 dollars monthly.
Tel: 447-4398
Fax: 3485269
小题1:If you don’t know how to use a computer, you can work as________.
A．a secretaryB．a waiter or waitress
C．an accountantD．a salesclerk
小题2:If you want to get a job in the Fairmont Hotel, you should be________.
A．a womanB．a university graduate
C．shorter than 1.65 metersD．younger than 30 years old
小题3:If you work as an accountant, how much can you get at most monthly?
A．$ 1, 800.B．$ 2,200.C．$ 3, 000.D．$ 4, 000.
小题4:If you want to be an accountant, you have to satisfy(满足) the following conditions except___________.
A．being a womanB．knowing how to use a computer well
C．an experience of at least 2 yearsD．having an accountant certificate
小题5:Sukan is 24 years old. He can get the job as_______.
A．a secretaryB．a waiter
C．an accountantD．a computer salesclerk
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实验题

（13分） CuSO4·5H2O是铜的重要化合物，有着广泛的应用。以下是CuSO4·5H2O的实验室制备流程图。

根据题意完成下列填空：

（1）向含铜粉的稀硫酸中滴加浓硝酸，在铜粉溶解时可以观察到的实验现象：                   、                            。

（2）有同学认为此种方法会生成有毒的氮的氧化物, 且所得晶体可能混有硝酸铜。建议将浓硝酸换成其它氧化剂，你觉得呢？若有同感，请选择合适的试剂完成下列反应（若有反应条件的应注明）：

__Cu + __H2SO4 + __________→ __CuSO4 +_______________

（3）已知：CuSO4+2NaOH=Cu(OH)2↓+ Na2SO4

相对分子质量：CuSO4：160       H2O：18

称取0.1000 g提纯后的CuSO4·5H2O试样于锥形瓶中，加入0.1000 mol/L氢氧化钠溶液28.00 mL，反应完全后，过量的氢氧化钠用0.1000 mol/L盐酸滴定至终点，耗用盐酸20.16 mL，则该试样中含CuSO4·5H2O的质量分数为        。

（4）上述滴定中，滴定管在注入盐酸之前，先用蒸馏水洗净，再用                                          。

（5）如果采用重量法测定CuSO4·5H2O的含量，完成下列步骤：

①称取样品a g②加水溶解③加氯化钡溶液，沉淀④过滤、        、干燥⑤称量所得固体b g。

在过滤前，需要检验是否沉淀完全，其操作是                           

则a g该试样中含CuSO4·5H2O的质量为              g （用含b的代数式表示）。

[相对原子质量：H-1   O-16  S-32   Ba-137]
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