若ax+1,ax+y,a3x(a>1,a≠1)成等比数列,则点(x,y)在平面直

题型:选择题

问题:

a
x+1
a
x+y
a
3x
(a>1,a≠1)
成等比数列,则点(x,y)在平面直角坐标系内的轨迹是(  )
A.一段圆弧B.抛物线的一部分
C.椭圆的一部分D.双曲线的一支的一部分
考点:等比数列的定义及性质动点的轨迹方程
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DNA复制的两大特点是 __________ 和 __________ 。

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- Mum's birthday is coming. I want to buy her something. Is there a _______ near here?

- Oh, yes! It's next to the bookshop.

A.gift shop

B.gifts shop

C.gift shops

D.gifts shops

题型:选择题

从舌苔的厚薄可()

A.了解病情的轻重和病情的进退

B.了解津液的变化

C.了解正邪斗争消长的情况

D.了解胃气的有无

E.了解病性的寒热

题型:选择题

It is hardly surprising that clothing manufacturers(生产商) follow certain uniform standards for various features of clothes.What seems strange, however, is that the standard adopted for women is the opposite of the one for men.Take a look at the way your clothes button.Men’s clothes tend to button from the right, and women’s form the left.Considering most of the word’s population----men and women----are right-handed, the men’s standard would appear to make more sense for women.So why do women’s clothes button from the left?

History really seems to matter here.Buttons first appeared only on the clothes of the rich in the 17th century, when rich women were dressed by servants.For the mostly right-handed servants, having women’s shirts button from the left would be easier.On the other hand, having men’s shirts button form the right made sense, too.Most men dressed themselves, and a sword drawn from the left with the right hand would be less likely to get caught in the shirt.

Today women are seldom dressed by servants, but buttoning form the left is still the standard for them.Is it interesting? Actually, a standard, once set, resists change.At a time when all women’s shirts buttoned form the left, it would have been risky for any single manufacturer to offer women’s shirts that buttoned from the right.After all, women had grown so used to shirts which buttoned from the left and would have to develop new habits and skills to switch.Besides, some women might have found it socially awkward to appear in public wearing shirts that buttoned from the right, since anyone who noticed that would believe they were wearing men’s shirts.

小题1:What is surprising about the standard of the clothing industry?

A.It has been followed by the industry for over 400 years.

B.It is different for men’s clothing and women’s.

C.It woks better with men than with women.

D.It fails to consider right-handed people.小题2:What do we know about the rich men in the 17th century?

A.They tended to wear clothes without buttons.

B.They were interested in the historical matters.

C.They were mostly dressed by servants.

D.They drew their swords from the left.小题3:Women’s clothes still button from the left today because        .

A.adopting men’s style is improper for women

B.manufacturers should follow standards

C.customs are hard to change

D.modern women dress themselves小题4:The passage is mainly developed by         .

A.analyzing causes

B.making comparisons

C.examining differences

D.following the time order

题型:选择题

夜间船舶在我国沿海航行,发现某浮标灯质为:快(6)+长闪15s,表明可航水域位于该标的()。

A.北侧

B.东侧

C.南侧

D.西侧

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