关于运动的合成,下列说法中正确的是[ ] A.两个直线运动的合运动一定是直线运动

题型:不定项选择

问题:

关于运动的合成,下列说法中正确的是[ ]

A.两个直线运动的合运动一定是直线运动

B.合运动的位移是分运动位移的矢量和

C.合运动的速度一定大于其中一个分运动的速度

D.合运动的时间一定是分运动时间之和

考点:运动的合成与分解
题型:不定项选择

阅读理解。

     Penguins lie together, but each pair has a little piece of ground of their own. When a penguin wants to walk

through its neighbour's ground, it must ask for permission. If it does not, it will have to fight. Penguins come

and go all day. They catch fish and look after their children.

      All penguins are good parents- the male penguins are perhaps the best parents in the world. They walk in

the middle of the dark Antarctic water. They choose their wives in the dark. They can only hear them-not see

them. Then the female penguins lay their eggs and go away for about two months. The males look after the

eggs. If the eggs get cold, there will be no chicks. There is no food. The snow falls and the wind

blows-sometimes at 150 kilometres an hour. The penguins do not move. When females return from the sea,

they will not remember their husbands. It does not matter. Only one thing matters - the eggs. Male penguins

never fight unless a penguin leaves a chick for a minute. Then they fight because they all want it. They are

strange and wonderful birds.

1. It seems interesting and unusual that the male penguins choose their wives ______.

A. when the female penguins return from the sea

B. just by hearing in the darkness

C. each time they see the lovely females

D. after they have had their own grounds

2. It is ______ that take care of the eggs.

A. the male penguins

B. the female penguins

C. both the husbands and the wives

D. the penguins that lost in the fight

3. Only when ______ can a penguin walk through its neighbour's ground.

A. it gets wet

B. it has become a father

C. it gets married

D. it gets permission

4. When the females return from the sea, they will ______.

A. live with their husbands

B. look after the eggs

C. get food for their husbands and children

D. not remember their husbands

5. Which of the following statements is NOT true?

A. Female penguins often have their new husbands.

B. Male penguins fight when choosing their wives.

C. Female penguins take care of the eggs.

D. Male penguins use their ears to choose wives.

题型:不定项选择
已知有穷数列{an}共有2k项(整数k≥2),首项a1=2.设该数列的前n项和为Sn,且an+1=(a-1)Sn+2(n=1,2,┅,2k-1),其中常数a>1.
(1)求证:数列{an}是等比数列;
(2)若a=2^
2
2k-1
,数列{bn}满足bn=
1
n
log2(a1a2an)
(n=1,2,┅,2k),求数列{bn}的通项公式;
(3)若(2)中的数列{bn}满足不等式|b1-
3
2
|+|b2-
3
2
|+┅+|b2k-1-
3
2
|+|b2k-
3
2
|≤4,求k的值.
题型:不定项选择

适于全脑全脊髓照射的肿瘤是()。

A.脑转移瘤

B.幕下分化差的室管膜瘤

C.脑膜肉瘤

D.髓母细胞瘤

E.Ⅳ级星形细胞瘤

题型:不定项选择

某建筑公司2013年9月的资产负债简表如下:

另知,该公司8月末的流动资产为1000万元,9月末在岗职工300人,再就业的离退休人员20人,借用的外单位人员15人,保留劳动关系但已经离开本单位的职工15人。

该公司9月末的固定资产净值为()万元。

A.950

B.1260

C.310

D.874

题型:不定项选择

心功能按NYHA分级,心功能在Ⅰ、Ⅱ级时其治疗措施是().

A.应用洋地黄制剂加强心肌收缩力

B.应用利尿剂减轻心脏前负荷

C.应用血管扩张剂减轻心脏后负荷

D.适当休息,避免体力劳动,防治原发病与心力衰竭诱发因素

E.应用非洋地黄类的正性肌力药物(如多巴胺)

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