保护生物的多样性就是在下 * * 个层次采取保护战略和保护措施[ ] A.基因、物种、

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问题:

保护生物的多样性就是在下 * * 个层次采取保护战略和保护措施[ ]

A.基因、物种、生态系统

B.细胞、物种、生物圈

C.基因、染色体、细胞

D.物种、种群、生态系统

考点:生物的多样性与保护
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电阻是导体本身的一种______,它表示导体对______阻碍作用的大小.

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左心衰竭最早的表现是()

A.劳力型呼吸困难

B.咯血

C.肝大

D.水肿

E.发绀

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下列有关原子结构和元素周期律的表述正确的是( )。
①原子序数为15的元素的最高化合价为+3
②ⅦA族元素是同周期中非金属性最强的元素
③第2周期第ⅣA族元素的原子核电荷数和中子数一定为6
④原子序数为12的元素位于元素周期表的第3周期第ⅡA族

A.①②
B.①③
C.②④
D.③④

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Generally speaking, a British is widely regarded as a quiet, shy and conservative person who is (1) only among those with whom he is acquainted. When a stranger is at present, he often seems nervous, (2) embarrassed. You have to take a commuter train any morning or evening to (3) the truth of this. Serious-looking businessmen and women sit reading their newspapers or dozing in a corner; hardly anybody talks, since to do so would be considered quite offensive. (4) , there is an unwritten but clearly understood code of behavior which, (5) broken, makes the offender immediately the object of (6) .

It has been known as a fact that a British has a (7) for the discussion of their weather and that, if given a chance, he will talk about it (8) . Some people argue that it is because the British weather seldom (9) forecast and hence becomes a source of interest and (10) to everyone. This may be so. (11) a British cannot have much (12) in the weathermen, who, after promising fine, sunny weather for the following day, are often proved wrong (13) a cloud over the Atlantic brings rainy weather to all districts! The man in the street seems to be as accurate — or as inaccurate — as the weathermen in his (14) .

Foreigners may be surprised at the number of references (15) weather that the British make to each other in the course of a single day. Very often conversational greetings are (16) by comments on the weather. "Nice day, isn’t it" "Beautiful!" may well be heard instead of "Good morning, how are you" (17) the foreigner may consider this exaggerated and comic, it is worthwhile pointing out that it could be used to his advantage. (18) he wants to start a conversation with a British but is (19) to know where to begin, he could do well to mention the state of the weather. It is a safe subject which will (20) an answer from even the most reserved of the British.

17()

A. Since

B. Although

C. However

D. Only if

题型:选择题

小张的父亲在教育他时,常采用以下方式:每当他表达自己的观点时,父亲就训斥道:“不要与大人争辩,我过的桥比你走的路还长,很多事情等你长大了就会明白。”小张考试成绩下降时,父亲就少给零用钱。小张家长的教育方式属于( )。

A.权威性

B.专制性

C.纵容性

D.疏离性

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