爱因斯坦由光电效应的实验规律，猜测光具有粒子性，从而提出光子说．从科学研究的方法

化合物A(C₈H₈O₃)为无色液体，难溶于水，有特殊香味，从A出发，可发生图示的一系列反应，图中的化合物A硝化时可生成两种一硝基取代物，化合物D能使FeCl₃溶液显紫色，G能进行银镜反应。

试回答：

(1)写出A的结构简式：___________，(Ⅱ)的反应类型为___________。

(2)写出C→E的化学方程式：___________________； 写出D→H的化学方程式：_________________；写出E与银氨溶液反应的化学方程式________________。

(3)A有多种同分异构体，其中符合下列条件的同分异构体共有____种，写出其中一种的结构简式

_______________。

①遇FeCl₃呈紫色 ②在稀的酸、碱溶液中均能反应且产物与A在相同条件下的水解产物组成均不同

(4)A的符合(3)中条件的某种同分异构体的水解产物I，以任意比与C混合，只要混合物总物质的量一定，完全燃烧时生成的水的量是一个常数，下列有关说法中正确的是____

a．完全燃烧时消耗氧气的数量是个定值

b．I是乙酸

c．等物质的量的C、I完全燃烧时耗氧量前者多

d．I是CH₃CHO

阅读理解

     Competition. It's a simple word, yet a very complex word that covers many angles when it comes to

how gasoline prices are determined. It seems so easy to explain, but don't let that trick you-it's incredibly

difficult to explain and adequately understand.

     Say you're on a Sunday afternoon drive, and notice a gas station near you charging $3.50. Down the

road a few miles, that price could easily be 10 or more cents higher or lower. The question is "how" or

"why" is that? Think of it this way. Are you more likely to get a better deal on a car if there are two similar car dealers next to each other? Perhaps, because the dealers are too close. Say there is a third similar car dealer miles away. Is he going to be at the same level of competition and sell his cars for the same price as the two dealers next to each other? Likely not. He may charge more or less. Maybe people don't know

there are two other dealers down the road. Maybe the dealer is almost outside of the city and the land

value isn't as high, so his taxes aren't as high.

     These situations do take place at gas stations. And more factors can impact what a station will charge. Timing can greatly impact what price a station charges as well! Many motorists fail to realize that the price a station pays for gasoline changes daily. If one station gets lucky and buys gas on Monday and the cost

goes up Tuesday, the station that bought on Monday doesn't necessarily have to raise prices like the

station that bought on Tuesday. Maybe the station that got caught buying for a higher price on Tuesday

will pass that higher cost on by raising its gas price.

      Perhaps the difference is what brand the station is-branded stations usually pay a slightly higher cost

for their gasoline. In return for paying a higher cost, those stations are guaranteed first supply in case of

emergency situations. Independent stations don't pay as much, but aren't guaranteed supply.

     While competition sounds easy to understand, there are always a large number of factors that could

influence what one station charges. Keep in mind how many variables (变数) there are next time you fill

up.

1. What could be the best title for the passage?

A. How Competition Impacts Gas Prices 

B. Gas Prices Go Up or Down

C. Competition---a Very Complex Word 

D. We Can't Stress Enough the Need for Competition  

2. The example of car dealers is used to show ________.  

A. car prices are determined by car dealers

B. location is an important factor in pricing

C. the quality of service matters most

D. dealing strategy should be flexible

3. The gas prices of a station always change partly because _______. 

A. a gas station always wants to charge more

B. the gasoline is in great demand

C. the cost of the gas the station buys varies daily

D. gas is in greater need on Monday

4. According to the passage, branded stations _______.

A. spend less money on their gasoline        

B. have more staff than independent stations

C. charge less for high quality oil            

D. offer a steady oil supply

《继电保护和安全自动装置基本试验方法》规定，一般使用仪表的准确度应根据被测量的误差等级进行选择。当被测量的误差＞1.5%~5%时，应选择准确度为（）级的仪表

A.0.1

B.0.2

C.0.5

D.1.0

下列对β受体阻断药治疗心力衰竭的药理依据的叙述正确的是（）

A.下调心肌的β受体

B.可拮抗过高的交感神经活性

C.加强心肌收缩性

D.减慢心率，减少心肌耗氧量

E.抑制RAAS系统

下列属于习 * * * * 对于原则性与灵活性的认识的是（）。

A.原则性与灵活性是可有可无、可大可小的问题

B.灵活具有绝对性，原则具有相对性

C.既不能用原则性限制灵活性，也不能用灵活性破坏原则性

D.原则性与灵活性是不能共存的