(5分)构建知识网络可以帮助我们理解知识间的内在联系。右图是盐酸与不同类别物质之

塑料基托颊侧的边缘形态，磨光后的要求应为（）

A.刃状形

B.半圆形

C.方圆形

D.斜坡形

E.以上都不对

在宏观、微观和符号之间建立联系是化学学科的特点。

（1）自然界中，由一百多种元素组成的几千万种物质都是由分子、原子或离子构成的（如下图）。现有氯化钠、氮气、镁三种物质，将其化学式填写在图中对应的位置。

（2）用化学符号表示：

①2个氢原子     ；    ②氩气     ；   ③氧化铝中铝元素的化合价     。

（3）写出下列反应的化学方程式：

①木炭在氧气中燃烧                                 ；

②加热氯酸钾和二氧化锰的混合物                                 ；

③某化学反应的微观模拟示意图如下：

该反应的化学方程式为                                 。

简述著作权法定许可使用的含义，至少举出两项法定许可使用的情形。

被认为较为满意的问卷调查的回收率应在______

A．60%以上
B．70%以上
C．80%以上
D．90%以上

In February of 1997 Dolly, the first successful mammalian clone, was born in Edinburgh, Scotland. With the extensive news coverage of this momentous event, the study of genetic engineering and recombinant DNA was thrown into the public spotlight.
(41)__________Much of this unfounded fear is based upon memories of poorly researched science fiction novels, fear of the unknown, and a "growing mistrust of science".
(42)__________For example, it will be possible for cows to be genetically engineered to produce pharmaceuticals in their milk. This means that vaccination shots and pills would become obsolete. Babies could be brought up immune to diseases by simply being fed this milk. Imagine the impact on the quality of life for people who live in third world countries like Somalia. Whole countries could be made healthy and immune to disease.
(43)__________Rice does not provide all of the nutrients that the body needs and in these countries other food is very scarce. If rice or bread, another major staple, are genetically engineered to contain additional necessary vitamins and minerals then we could go a long way towards wiping out malnutrition all over the world.
(44)__________Organ transplants and cosmetic procedures, like silicone breast implants, that may cause disease would soon cease to exist. Instead of using materials foreign to the body for such procedures, doctors will be able to manufacture bone, fat, connective tissue, or cartilage that match the patient’s tissues exactly, thus ensuring that the needed tissue will be free of rejection by their immune system. Victims of terrible accidents that deform the face and body would be able to have their features repaired with new, safer technology.
(45)__________
Throughout time people have always been afraid of new technology and the power it might possess. When the car was first invented some contemporary scientists were convinced that the human body could not survive at speeds as high as twenty miles per hour. At one time birth control pills, in vitro fertilization, and heart transplants were criticized on the same grounds.
Genetic engineering is an extremely new aspect of our technological research and should, at all costs, be allowed to develop further. The immense possible benefits from genetic engineering are endless and should not be overlooked. Genetic engineering, then, is a tool that humans can use to cure many of their problems.
[A] Even though the risks are great, the beneficial possibilities are endless. Genetic engineering should be allowed to progress because of the potential benefits for the human species outweigh the consequences.
[B] Scientists are only beginning to explore the dangers and benefits of genetic engineering. Yet, instead of seeing the immense potential benefits, much of the American public is automatically rejecting this field of research.
[C] Genetic engineering also has the power to cure infertility, which a painful reality that many couples throughout the world face.
[D] Even with all these miraculous benefits, many people throughout the world feel that the issue of genetic engineering is absolutely preposterous and extremely unethical. Such opinions are understandable, considering that the majority of people are always going to be afraid of the unknown.
[E] Malnutrition, a common problem in many third world countries where impoverished peoples rely on a single crop such as rice for the main staple of their diet, could also possibly be cured with genetic engineering.
[F] But perhaps, the area that stands to benefit the most from genetic engineering is medicine.
[G] Genetic engineering is like performing heart surgery with a shovel. Scientists do not yet understand living systems completely enough to perform DNA surgery without creating mutations which could be harmful to the environment and our health.