影片《城南旧事》的导演是（）。

物业管理区域绿化环境管理队伍的组成应包括（）等。

A.绿化环境管理队伍的管理者

B.绿化环境管理技术人员

C.技术工人

D.苗圃工作人员

如图所示，一个半径为R的透明圆柱体放置在水平面上，一束蓝光从A点沿水平方向垂直于左表面射入圆柱体后经B点射出，最后射到水平面上的C点。已知OA＝，该圆柱体对蓝光的折射率为，则它从右侧面射出时的出射角β＝________；若将蓝光换成紫光，则它从圆柱体射出后落到水平面上形成的光点与C点相比，位置________(选填“偏左”、“偏右”或“不变”)。

2004年11月12日为著名的宗教领袖、民族解放运动领袖阿拉法特举行了隆重葬礼。所在地的矛盾是（）

A、巴以冲突

B、车臣问题

C、科索沃战争

D、印巴争端

直升机在执行通用航空飞行任务时，起飞油量等于（）。

A.（起飞机场至临时机场的飞行时间+50分钟）×每小时平均耗油量

B.（起飞机场至临时机场的飞行时间+30分钟）×每小时平均耗油量

C.（起飞机场至临时机场的飞行时间+20分钟）×每小时平均耗油量

D.（起飞机场至临时机场的飞行时间+10分钟）×每小时平均耗油量

Despite increased airport security since September 11th, 2001, the technology to scan both passengers and baggage for weapons and bombs remains largely unchanged. Travellers walk through metal detectors and carry-on bags pass through x-ray machines that superimpose colour-coded highlights, but do little else. Checked-in luggage is screened by "computed tomography", which peers inside a suitcase rather like a CAT scan of a brain. These systems can alert an operator to something suspicious, but they cannot tell what it is.

More sophisticated screening technologies are emerging, albeit slowly. There are three main approaches: enhanced x-rays to spot hidden objects, sensor technology to sniff dangerous chemicals, and radio frequencies that can identify liquids and solids. A number of manufacturers are using "reflective" or "backscatter" x-rays that can be calibrated to see objects through clothing. They can spot things that a metal detector may not, such as a ceramic knife or plastic explosives. But some people think they can reveal too much. In America, civil-liberties groups have stalled the introduction of such equipment, arguing that it is too intrusive. To protect travellers’ modesty, filters have been created to blur genital areas.

Machines that can detect minute traces of explosive are also being tested. Passengers walk through a machine that blows a burst of air, intended to dislodge molecules of substances on a person’s body and clothes. The air is sucked into a filter, which instantaneously analyses it to see whether it includes any suspect substances. The process can work for baggage as well. It is a vast improvement on today’s method, whereby carry-on items are occasionally swabbed and screened for traces of explosives. Because this is a manual operation, only a small share of bags are examined this way.

The most radical of the new approaches uses "quadrupole resonance technology". This involves bombarding an object with radio waves. By reading the returning signals, the machines can identify the molecular structure of the materials it contains. Since every compound--solid, liquid or gas--creates a unique frequency, it can be read like a fingerprint. The system can be used to look for drugs as well as explosives.

For these technologies to make the jump from development labs and small trials to full deployment at airports they must be available at a price that airports are prepared to pay. They must also be easy to use, take up little space and provide quick results, says Chris Yates, a security expert with Jane’s Airport Review. Norman Shanks, an airport security expert, says adding the new technologies costs around $ 100 000 per machine; he expects the systems to be rolled out commercially over the next 12 months. They might close off one route to destroying an airliner, but a cruel certainty is that terrorists will try to find others.

What is the relationship between the 2nd paragraph and the 3rd, 4th and 5th paragraphs（）

A. A generalization is made in paragraph 2 and then elaborated in paragraph 3,4 and 5

B. More sophisticated screening technologies are mentioned in paragraph 2 and 3 and then examples are provided in paragraph 4 and 5

C. Specific evidence is provided in paragraph 1,2 and 3 and then a conclusion is drawn in paragraph 4

D. Three main approaches are advanced in paragraph 2,3 and then their functions are detailed in paragraph 4 and 5