438+2.25+558+734.

题型:解答题

问题:

4
3
8
+2.25+5
5
8
+7
3
4
考点:运算定律和简便算法
题型:解答题

下列关于西欧列强早期殖民扩张的表述不正确的是 [ ]

A.推动了西欧资本原始积累的进程        

B.主要目的是为了寻求和扩大资本输出     

C.推动了世界市场的进一步拓展          

D.给亚非拉人民带来深重的灾难 

题型:解答题

Few creatures on earth are as cute as the black lion tamarin, and few have as dramatic a story line. Pug-nosed and diminutive, with a comic fringe of hair, these monkeys dwell in trees in small tracts of forest in southeastern Brazil. Or they did until 1905, when they were declared extinct. No one saw a black lion tamarin again in the wild until 1970. Later, in the 1990s, some Brazilian researchers turned up a small set of isolated, inbred populations scattered over a wide region. Since that time, they have been engineering tamarin migration, doing everything they can to save the world’s most distinctive primates.
Although they are no larger than house cats, tamarins have brains big for their size and a family life organized like our own. They live in groups anchored by an adult male andadult female, along with their offspring. When a mother bears young, she usually produces twins, and although members of the group share in their upbringing, it is most often the father who carries them around in the trees, where the families feed on fruits, insects and bird’s eggs.
Unhappily for the lion tamarins, their tree-bound niche began to disappear after the Portuguese landed in Brazil and began clearing forest to make room for Rio de Janeiro, the settlements and farms. As is the case for so many threatened species, the breakup of their habitat sounded the death knell for tamarins, depriving them of the continuity of forest they require to remain abundant and safe from potential threats in any single vicinity. The animals avoid predators by hardly ever coming down from the trees, so even a narrow logging road through a forest can begin the breakup by preventing them from moving from one patch of forest to another.
A simple solution was to build bridges across roads, allowing the monkeys to move from one forest to another. With some lumber and the researchers’ work, habitats that had been separated became continuous again, improving opportunities for migrating and mating.
The next step was to broaden the distribution of the population. The researchers captured two families of black lion tamarins and moved them to a new forest. After a year, the moves were declared a success: Not only had 80 percent of the tamarins survived, but they had also produced new offspring. So far, so good. The researchers had learned the animals could adjust to the new habitats, even if the insects there tasted a little different or the trees were a slightly different size.
The techniques for saving species in the wild vary. Species with less stringent habitat requirements, like wild turkeys, have been rescued by moving them into new settings as well as outlawing their killing. More challenging to preserve are species that require a lot of land, like elephants, and species that have highly specific requirements for habitat and prey -- like black-footed ferrets. Ultimately, as in all challenges, knowledge is power to save wild species from extinction.

A tamarin can be called any of the following EXCEPT ______.

A.a monkey

B.a primate

C.a house cat

D.a lion tamarin

题型:解答题

中国古代帝王陵的地面建筑主要由山门、神道和护陵监三部分构成。

题型:解答题

回墨板一般为底面光滑的金属刮板,其宽度应()刮墨板。

A、稍大于

B、稍小于

C、等于

D、无所谓

题型:解答题

脘腹痞满胀痛,嗳腐吞酸,恶食呕恶,舌苔厚腻微黄,脉滑,治疗宜选用()

A.枳实消痞丸

B.保和丸

C.枳实导滞丸

D.健脾丸

E.木香槟榔丸

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