如果完工比例是60%，完工预算是20000美元，实际成本（实际成本或已完成工作实际成

If you ________ the lions, you will become a great soccer player.[ ]

A. join

B. will join

C. take part in

D. will take part in

CAT的含义是( )。

A．计算机辅助设计

B．计算机辅助工程

C．计算机辅助制造

D．计算机辅助测试

（15分）

由碳、氢、氧三种元素组成的某有机物X的相对分子质量为136，其中碳、氢元素的质量分数之和为76.5﹪.又知X中含有甲基，苯环上的一氯代物有两种。X经热的酸性KMnO₄溶液处理后转化为Y,1mol Y与足量NaHCO₃溶液反应生成标准状态下44.8L CO₂气体。

据此完成下列要求。

（1）X中含氧官能团的名称为                 ，1mol Y最多可与                mol Na反应。

（2）已知A、B、C、D均与X互为同分异构体，且均是有一个取代基的芳香族化合物，其中B可以发生银镜反应。相关转化关系如下图。

①A的结构简式为                 。A～K的各有机物中，属于酸的是                 （填字母）。

②C与足量的NaOH溶液加热时发生反应的化学方程式为：                 ，该反应中涉及到的有机反应类型为                 。

③属于芳香族化合物的E的同分异构体有                种（不含E）。

④足量的G与Y在一定条件下发生反应的化学方程式为：                        。

取消投资津贴和增加所得税都属于紧缩性财政政策。( )

Plants can’t communicate by moving or making sounds, as most animals do. Instead, plants Produce volatile compounds, chemicals that easily change from a liquid to a gas. A flower’s sweet smell, for example, comes from volatile compounds that the plant produces to attract insects such as Bugs and bees.

Plants can also detect volatile compounds produced by other plants. A tree under attack by Hungry insets, for instance, may give off volatile compounds that let other trees know about the Attack. In response, the other trees may send off chemicals to keep the bugs away ——or even  Chemicals that attract the bugs’ natural enemies.

Now scientists have created a quick way to understand what plants are saying: a chemical Sensor（传感器）called an electronic nose. The “e-nose” can tell compounds that crop plants make When they’re attacked Scientists say the e-nose could help quickly detect whether plants are being Eaten by insects. But today the only way to detect such insects is to visually inspect individual Plants. This is a challenging task for managers of greenhouses, enclosed gardens than can house Thousands of plants.

The research team worked with an e-nose than recognizes volatile compounds. Inside the device, 13 sensors chemically react with volatile compounds Based on these interactions, the e-nose gives off electronic signals that the scientists analyze using computer software.

To test the nose, the team presented it with healthy leaves from cucumber, pepper and tomato plants, all common greenhouse crops. Then scientists collected samples of air around damaged leaves from each type of crop, These plants had been damaged by insects, or by scientists who made holes in the leaves with a hole punch（打孔器）. The e-nose, it turns out, could identify healthy cucumber, pepper and tomato plants based on The volatile compounds they produce, It could also identify tomato leaves that had been damaged. But even more impressive, the device could tell which type of damage ---- by insects or with a hole Punch ---- had been done to the tomato leaves.

With some fine-tuning, a device like the e-nose could one day be used in greenhouses to quickly spot harmful bugs, the researchers say. A device like this could also be used to identify fruits that are perfectly ripe and ready to pick and eat, says Natalia Dudareva, a biochemist at Purdue University in West Lafayette, Ind. who studies smells of flowers and plants. Hopefully, scientists believe, the device could bring large benefits to greenhouse managers in the near future.

小题1:We learn from the text that plants communicate with each other by____.

A．making some sounds

B．waving their leaves

C．producing some chemicals

D．sending out electronic signals小题2:What did the scientists do to find out if the e-nose worked?

A．They presented it with all common crops.

B．They fixed 13 sensors inside the device.

C．They collected different damaged leaves.

D．They made tests on damaged and healthy leaves.小题3:According to the writer, the most amazing thing about the e-nose is that it can___.

A．pick out ripe fruits

B．spot the insects quickly

C．distinguish different damages to the leaves

D．recognize unhealthy tomato leaves小题4:We can infer from the last paragraph that the e-nose_____.

A．is unable to tell the smell of flowers

B．is not yet used in greenhouses

C．is designed by scientists at Purdue

D．is helpful in killing harmful insects