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问题 填空题

某同学在做“研究匀变速直线运动”的实验时：

（1）实验室提供了下列的实验器材：

①打点计时器②天平③导线和电源④细绳和纸带⑤钩码和小车⑥秒表⑦一端有滑轮的长木板⑧刻度尺

则该同学不需要选用的器材有（写代号）：______

（2）在该实验中，小车拖着纸带通过记录下的运动情况如图所示，图中O、A、B、C、D、E为连续选定的计数点，相邻计数点间的时间间隔是0.10s，标出的数据单位是cm，则在打C点时小车的速度是______m/s．

答案

（1）在本实验中不需要测量小车质量因此不需要天平，同时打点计时器记录了小车运动时间，因此不需要秒表．

故不需要选用的器材有：②⑥．

（2）根据匀变速直线运动中时间中点的速度等于该过程中的平均速度，可以求出打纸带上D点时小车的瞬时速度大小．

vC=

XBD
2T
=
0.384-0.128
0.2
=1.28m/s

故答案为：（1）②⑥

（2）1.28

阅读理解
Your school has planned a visit to Lions Nature Education Centre. Here is what you should know about the centre. Please read it.
Lions Nature Education Centre
Lions Nature Education Centre opened in 1991 on what was once a government farm in Sai Kung. Both the government and the Lions Club own it now.
Aims
The aim of the centre is to show visitors everything to do with rural (乡下的) Hong Kong. We also hope to educate people about the environment. For this reason, it’s really a popular place for school trips and outings.
Facilities (设施)
The centre has a large number of indoor and outdoor facilities and exhibitions (展品). The outdoor facilities include a garden, vegetable fields and a place where trees are grown for study. Indoor exhibition halls provide different kinds of plants, fishes and other things from land or sea. The Farmers’ Market is open at weekends.
Rules for visitors
·Wear proper clothes, shoes and hats.
·Bring some water and food, but take your rubbish away with you.
·Do not break any natural appearance or plants, and do not make the water dirty.
·Care for other visitors and wildlife (野生动植物), and do keep quiet wherever you go.
Opening hours

We are open daily from 9:30 am to 5:00 pm. Exhibition halls are open from 9:30 am to 4:30 pm. The centre is closed every Tuesday.
Address: Hiram’s Highway, Sai Kung
Phone: 2792 2234
Website: http://www.hknature.net/lnec
小题1:You can visit Lions Nature Education Centre            .
A．in the city centreB．at Hiram’s Highway
C．on a government farmD．inside the exhibition halls
小题2:In the centre, visitors can learn about            .
A．rural clothes and shoesB．different kinds of seafood
C．outdoor lions in natureD．the environment around us
小题3:Before your school go to the centre, you should tell them            .
A．not to visit the Farmers’ MarketB．not to make a noise or wear hats
C．to care for the wildlife and waterD．to look for rubbish and take it away
小题4:Lions Nature Education Centre is closed            .
A．at weekendsB．after 4:30 pm
C．during weekdaysD．before 9:30am
小题5:For more information about the centre, you’d better            .
A．call at 2792 2234B．ask other visitors
C．study the facilitiesD．provide the website
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单项选择题

某超市为增值税小规模纳税人。2008年1月，该超市取得货物零售收入120000元；向困难群体捐赠部分外购商品，捐赠商品的买价为4200元，售价为5000元；向职工发放部分外购商品作为节日福利，发放商品的买价为3000元，售价为3700元；本期购进税控机器取得增值税普通发票，注明价税合计12800元。该超市当月应纳增值税( )元。

A．2273.50
B．4807.69
C．2947.86
D．4950.00
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