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问题 选择题

下列对催化剂的描述不正确的是（　　）

A．化学反应前后质量不变

B．化学反应前后化学性质不变

C．化学反应前后物理性质不变

D．改变了化学反应速率

答案

催化剂能改变其他物质的反应速率，催化剂的特点是：在反应前后质量和化学性质都没有发生变化．

 故选C．

阅读理解

Take a look at the following advertisements! You may find some useful information you need here!

Guitar lessons
Experienced musician from Australia. Good at teaching kids for many years! For more information, please visit Larry’s website: www.music.com.au.

Lost dog
Medium size, with brown spots and white short hair. Answer you when you call it David. Many thanks for sending it back. Call at 7328059.

Taxi driver wanted
Full time or part time. Good knowledge of the city is necessary. English is also a must. Under 45 years old. Call Mr White at 5132683.

House for sale
Two bedrooms, a kitchen and a bathroom. Hot water 8:00 am-6:00 pm.
Beautiful sights out of the windows.
Write to Mr Black. E-mail: sdgt@163.com
小题1:You may visit www.music.com.au to _________.
A．buy a big house
B．know about guitar lesson
C．find the lost dog
D．get a part-time job
小题2:If you are interested in the house, you can write to _______.
A．LarryB．DavidC．Mr BlackD．Mr White
小题3:You can call 5132683 to get the job as _______.
A．a taxi driverB．a dog keeperC．a guitar teacherD．a house seller
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解答题

生产一批零件，计划每天生产160个，15天可以完成，实际每天超产80个，可以提前几天完成？（用比例方法解）
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