蝇与传播疾病有关的形态与生活习性有哪些？

在“用单摆测定重力加速度”的实验中，用刻度尺量悬点到小球的距离为96.60cm，用卡尺量得小球直径是5.260cm，测量周期有3次，每次都在摆球通过最低点时按下秒表开始计时，同时将此次通过最低点作为第一次，接着一直数到计时终止，结果如下表：

这个单摆振动周期的测量值是____________s，当地重力加速度的值是____________m/s²。（取三位有效数字）

E

Many do-it-yourself homeowners are interested in

trying out solar power to leam about the technology and

perhaps to provide energy for limited-use applications．

There are a variety of ways to find cheap solar panels

（板）, including buying used and building your own

with factory seconds．Both methods will save money

while forcing you to learn the ins-and-outs of a solar

power array （阵列）．  

We've all seen solar-powered street signs or PV

panels being used for various purposes at remote locations．

When those units become cracked or chipped and are considered "unsafe", companies are forced to replace them, generally to avoid responsibility issues．Because it's difficult to get rid of PV panels, many companies, if approached, are willing to give them away or to sell them for modest prices．Depending on the degree of damage present, expect to see performance degradation （降级） in the range of 10% to 60%．A multimeter （万用表） can be used to test the panel before buying．If the panel's free, take it anyway．It could still be useful in a home solar project．

A solar panel is really nothing but a box serving as a container for a large group of solar cells．Factory second solar cells are usually sold on eBay at a small part of their regular cost．The cells come in a variety of sizes．You will need to figure out how much power a single cell produces to determine how many will need to be wired together to form an array．

A simple search of the Internet will show numerous sites detailing home solar panel projects．Do-it-yourself lovers are generally quite generous in supply photographs of their work and description of what went wrong and right with the project．

Getting cheap solar panels with slight imperfections, either used or through sales of factory seconds, is a perfect solution for home-built renewable energy projects．The high number of solar lovers online provide a wealth of useful information．Only limited skills are required, plus an understanding of the basic wiring involved．All are well within the talents of almost any home handyman．Beyond the satisfaction of having completed the project, you'll come away with a functional solar panel that will be a source of power for use around the house or at remote locations．

Solar energy systems are quickly becoming more popular with homeowners as prices continue to decline．

72．The author writes the passage to introduce ____．

A．ways of finding cheap solar panels B．ways of saving energy

C．a way of making a solar panel     D．a home-built energy system

73．What does the phrase "factory seconds" in the passage refer to?

A．Second-hand factory products．  B．Cheap but perfect factory products

C．Faulty factory solar cells．        D．The second best factory solar cells

74．From Paragraph 5, we can learn about home-built energy projects that ____．

A．none of them are beyond home handymen

B．a lot of useful information is available on the Internet

C．a perfect solution is to get cheap and perfect solar panels

D．understanding electrical wiring is not necessarily needed

75．What is the author's attitude towards the future of solar energy systems?

A．Optimistic．  B．Pessimistic.      C．Indifferent．         D．Doubtful

2010年12月当月，全国实际使用外资金额140.3亿美元，同比增长15.6%。2010年全年全国非金融领域新批设立外商投资企业27406家，同比增长16.9%；实际使用外资金额1057.4亿美元，同比增长17.4%，首次突破1000亿美元，创历史最高水平，同时扭转了2009年下降2.6%的局面。从结构来看，实际使用外资金额的较快发展主要得益于服务业以及中西部地区吸收外资的大幅增长，增幅分别为28.6%和27.6%。
2010年全年，服务业新设立外商投资企业13905家，同比增长21.3%，实际使用外资金额487.1亿美元，同比增长28.6%，占同期全国非金融领域新设立企业数和实际使用外资金额的比重为50.7%和46.1%；制造业新设立企业11047家，同比增长13.1%，实际使用外资金额495.9亿美元，同比增长6%，占同期全国非金融领域新设立企业数和实际使用外资金额的比重为40.3%和46.9%；外商投资农林牧渔业新设立外商投资企业929家，同比增长3.7%，实际使用外资金额19.12亿美元，同比增长33.8%。
2010年全年，东部地区新设立外商投资企业22992家，实际使用外资金额898.5亿美元，同比分别增长16.7%和15.8%；中部地区新设立外商投资企业3056家，实际使用外资金额68.6亿美元，同比分别增长16.4%和28.6%；西部地区新设立外商投资企业1358家，实际使用外资金额90.2亿美元，同比分别增长22.3%和26.9%。东、中、西部地区实际使用外资占全国的比重分别为85%、6.5%和8.5%，分别比去年同期降低1.2个百分点、增加0.6个百分点和增加0.6个百分点。

2009年东部地区实际使用外资金额是西部地区的多少倍

A．10.9倍

B．8.4倍

C．14.8倍

D．9.6倍

大体积混凝土不宜采用的水泥是()。

A.硅酸盐水泥

B.普通硅酸盐水泥

C.矿渣水泥

D.粉煤灰水泥

E.火山灰水泥

每升输液中含钾量最多可用至（）

A.1g

B.2g

C.3g

D.4g

E.5g