已知{an}是等比数列,且an>0,a2a4+2a3a5+a4a6=25,那么a

题型:填空题

问题:

已知{an}是等比数列,且an>0,a2a4+2a3a5+a4a6=25,那么a3+a5的值等于______.

考点:等比数列的定义及性质
题型:填空题

下列各项中不属于无性生殖的是[     ]

A.利用根繁殖

B.利用茎繁殖

C.利用叶繁殖

D.利用种子繁殖

题型:填空题

第二节 完形填空(共20 小题;每小题1.5分,满分30分)

阅读下面短文,从短文后各题所给的四个选项(A 、B、 C 和D)中,选出可以填入空白处的最佳选项,并在答题卡上将该项涂黑。

"Dr. Papaderos, what is the meaning of life?"

The _36___ laughter followed, and people stirred to go.

Papadakos held up his hand and __37___ the room and stared at me, asking with his eyes if I was serious and seeing from my eyes __38___ I was.

"I will answer your question."

Taking his wallet out of his hip pocket, he __39___ into it and brought out a very small round ___40__.

And what he said ___41__ like this:

"When I was a small child, during the war, we were very poor and lived _42__in a remote village. One day, on the road, I found the broken pieces of a mirror from a wrecked German motorcycle. "I tried to find all the pieces and put them together, but it was not__43___, so I kept only the largest piece. I made it round. I began to play with it as a ___44__, interested by the __45___ that I could reflect light into dark places where the sun would ___46__ shine. It became a game for me to get light into the most__47____ places I could find---in deep holes and dark closets.

I kept the little mirror, and, __48___ I went about my growing up, I would take it out in idle moments and continue the ___49___ of the game. As I became a man, I __50___ to understand that this was not just a child's game but a metaphor (隐喻) for what I might do __51___ my life. I came to understand that I am not the light or the ___52__ of light. But light---truth, understanding, knowledge---is there, and it will shine in many dark places __53____ I reflect it.

"I am a fragment (碎片)of a mirror whose whole design and shape I do not know.__54____, with what I have I can reflect light into the black places in the ___55___ of men. This is the meaning of my life."

36. A. common    B. usual     C. ordinary   D. general

37. A .cheered     B. stopped   C .stilled     D. cleaned 

38. A .that        B. what      C. where    D. whether

39. A. fished      B. looked    C dipped     D. slipped    

40.A. coin        B. toy       C. mirror    D. present

41.A. came       B. sounded    C. read     D. went

42. A. hopefully   B. peacefully  C. hopelessly  D. plainly

43.A. possible     B. difficult   C. easy       D. reasonable

44.A.child        B .treasure   C. tool       D. toy

45.A.case        B. truth       C .fact       D. result

46. A. always     B. seldom     C. still        D. never

47 .A .unavailable  B. difficult    C. interesting  D.  inaccessible

48. A. as          B. before     C. after       D. while

49.A .difficulty    B .challenge   C. content     D. rule

50 .A. grew       B. tended     C. used       D. failed

51. A. for         B. to        C. about        D .with 

52 .A. player       B. resource  C. origin       D. source

53.A. if only       B. only if    C. as far as     D. now that

54. A. Therefore    B. Otherwise  C. However   D. Besides

55. A. hearts       B. minds     C. eyes       D. brains

题型:填空题

试述政策议程建立的条件。

题型:填空题

下颌种植修复需拔牙后多久进行()

A.1周

B.1个月

C.3个月

D.3~4个月

E.5~6个月

题型:填空题

国际邮件按照运输方式分为:航空邮件、()和空运水陆路邮件。

A.SAL

B.特快专递邮件

C.水陆路邮件

D.陆路邮件

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