麦当劳之所以能够成为服务业执牛耳的公司，就是狠狠地把握了服务的（）。 A.细节性 B

某省人大为了整治校园环境依法制定了《某省整治校园环境条例》，后来因一起案例，有关部门审查发现该条例与教育部的某一有效规章规定不一致，不能确定如何使用，那么：( )。

A．国务院认为应当适用地方性法规的，应当决定在该地方适用地方性法规的规定

B．国务院认为应当适用部门规章的，应当决定在该地方适用部门规章的规定

C．由国务院裁决

D．由全国人民代表大会常务委员会裁决

根据《民法通则》的规定，下列关于民事法律行为的表述错误的是( )。

A．无效的民事行为，从行为开始时就没有法律约束力
B．被撤销的民事行为，从行为开始起无效
C．民事行为部分无效，不影响其他部分效力的，其他部分仍然有效
D．显失公平的民事行为无效

装设平波电抗器的目的是什么（）

A.减小注入直流系统的谐波电流

B.抑制直流短路电流

C.防止轻载时直流电流断续

D.减少投资

Scattered through the seas of the world are billions of tons of small plants and animals called plankton (浮游生物). Most of these plants and animals are too small for the human eye to see. They drift about lazily with the currents, providing a basic food for many larger animals. Plankton has been described as the equivalent of grasses that grow on the dry land continents, and the comparison is an appropriate one. In the potential food value, however, plankton far outweighs that of the land grasses. One scientist has estimated that while grasses of the world produce about 49 billion tons of valuable carbohydrates (碳水化合物) each year, the sea’s plankton generates more than twice as much.

Despite its enormous food potential, little effort was made until recently to farm plankton as we farm grasses on land. Now, marine scientists have at least begun to study this possibility, especially as the sea’s resources appear even more important as a means of feeding an expanding world population.

No one yet has seriously suggested the "planktonburger" may soon become as popular as hamburger around the world. As a possible farmed supplementary food source, however, plankton is gaining considerable interest among marine scientists.

One type of plankton that seems to have great harvest possibility is a tiny shrimp-like creature called krill (磷虾). Growing to two or three inches long, krill provide the major food for the giant blue whale, the largest animal on Earth. Realizing that this whale may grow to 100 feet and weigh 150 tons at maturity, it is not surprising that each one consumes more than one ton of krill daily. Krill swim about just below the surface in huge schools sometimes miles wide, mainly in the cold Antarctic. Because of their pink color, they often appear as a solid reddish mass when viewed from a ship or from air. Krill are very high in food value. A pound of them contains about 460 calories-about the same as shrimp or lobster, to which they are related.

If the krill can feed such huge creatures as whales, many scientists reason, they must certainly be candidates as a new food source for humans.

Why does the author mention "planktonburgers" in paragraph 3（）

A. To describe the appearance of one type of plankton.

B. To illustrate how much plankton a whale consumes.

C. To suggest plankton as a possible food source.

D. To compare food values of beef and plankton.

明朝在防御蒙古贵族方面采取了哪些重大措施其代价和影响如何