货币可自由兑换的条件是什么？

选答题

Ⅱ．论述教育观察研究方法的优缺点。

Part B (10 points)

You are going to read a list of headings and a text about happiness. Choose the most suitable heading from the list A—F for each numbered paragraph (41—45). The first and last paragraphs of the text are not numbered. There is one extra heading which you do not need to use.

A. Extensive applications of haptic technology.

B. Possibilities rendered by haptic mechanisms.

C. The feasibility of extending our senses and exploring abstract universes.

D. An example of the progress in science of haptics.

E. Bringing the potential of our senses into full play.

F. Will haptics step into a bright future？

"OOOF!" Using your mouse, you heave a data file across the screen—a couple of gigabytes of data weigh a lot. Its rough surface tells you that it is a graphics file. Having tipped this huge pile of data into a hopper that sends it to the right program, you examine a screen image of the forest trail you'll be hiking on your vacation. Then, using a gloved hand, you master its details by running your fingers over its forks and bends, its sharp rises and falls. Later you send an E-mail to your beloved, bending to the deskpad to attach a kiss.

(41)______.

The science of haptics (from the Greek haptesthai, "to touch") is making these fantasies real. A few primitive devices are extending human-machine communication beyond vision and sound. Haptic joysticks and steering wheels for computer games are already giving happy players some of the sensations of piloting a spaceship, driving a racing car or firing weapons. In time, haptic interfaces may allow us to manipulate single molecules, feel clouds and galaxies, even reach into higher dimensions to grasp the subtle structures of mathematics.

(42)______.

Most of our senses tire passive. In hearing and vision, for example, the sound or light is simply received and analyzed. But touch is different: we actively explore and alter reality with our hands, so the same action that gathers information can also change the world—to model a piece of clay or press a button, for example. In providing direct contact between people, touch carries emotional impact. And in providing direct contact with the world, it is the sure sign of reality, as in "pinch me—am I dreaming？"

(43)______.

Some small steps have even been taken towards whole-body haptics. Touch Technology of Nova Scotia, Canada, has built a haptic chair. It looks like a full-length lounge chair in a family den, but its surface is studded with 72 "tactors" -pneumatic piston rods, covered with rounded buttons, that can extend about an inch, and can be driven under computer control in any desired sequence and pattern. It could be programmed to imitate a real massage or to function in time to music. According to the manufacturer, that provides a powerful blending of sensations—a long-term goal of virtual reality.

(44)______.

Even at its present crude level, however, haptics can make tangible what once could not be touched or even pictured. To investigate the world of the very small, researchers at the University of North Carolina, Chapel Hill, have developed the nanoManipulator. This adds touch to the technique of scanning probe microscopy, which can image a single atom by monitoring either the electrical current flowing between an extremely fine probe and a surface or the force between them. With the nanoManipulator, researchers can see and manipulate a universe a million times smaller than their own, to study viruses and tiny semiconducting devices. If the force feedback can be made sensitive enough, it may be possible to push molecular keys into specific molecular locks, to custom-design drugs or assemble silicon parts into intricate nanomachines. With other interfaces, there is no reason we shouldn't also be able to touch the very large-clouds, ocean

已知某产品的需求函数为Qd=60-2P，供给函数为Qs=30+3P。

(1)求均衡点的需求弹性和供给弹性。

(2)如果政府对每一件产品课以5元的销售税，政府的税收收入是多少，其中生产者和消费者各分担多少？

假定经济满足Y=C+I+G，且消费C=800+0.63Y，投资I=7500-20000r，货币需求L=0.1625Y-10000r，名义货币供给量6000亿元，价格水平为1，问当政府支出从7500亿增加到8500亿时，政府支出的挤出效应有多大？请结合中国财政政策的实际情况加以分析。

2005年7月21日中国政府宣布人民币汇率改革，放弃盯住美元，并允许人民币汇率浮动，人民币币值就开始了几乎单边升值的过程。至2008年7月31日，3年采人民币对美元升值幅度已超过21%。该态势虽然暂时缓解了外国政府(以美国为主)对中国汇率政策的压力，但是人民币升值的压力和预期并没有明显减弱的迹象，长此以往将对我国经济和金融体系产生严重的负面影响。试分析人民币升值预期的成因，判断其对我国经济的影响，如何缓解升值预期？