求圆锥曲线3x2-y2+6x+2y-1=0的离心率．

下列关于土地使用权租赁，说法错误的是（）。

A.土地使用权租赁双方当事人只是就使用土地达成协议，不发生作为物权的土地使用权的转移

B.土地使用权租赁合同是有偿合同

C.如果民事主体无合法原因擅自租赁土地（例如划拨取得的土地使用权），仍属于合法行为

D.当出租的土地使用权发生转移时，新的土地使用权人也必须尊重承租人的合法权利

某种细菌在培养过程中，每半小时分裂1次，每次一分为二．若这种细菌由1个分裂到16个，那么这个过程要经过（　　）

A．1.5小时

B．2小时

C．3小时

D．4小时

An analysis by Mount Sinai researchers of over eight years of dietary data from more than 400,000 people has found that the relationship between high consumption of fruits and vegetables and a reduced risk of cancer is not as strong as commonly thought. The study is published online April 6, 2010 in the Journal of the National Cancer Institute. It is widely believed that a diet rich in fruits and vegetables can reduce the risk of cancer. In 1990, the WHO recommended eating five servings of fruits and vegetables a day to prevent cancer and other diseases. However, although many studies have been conducted since then, none have been able to confirm an association between fruit and vegetable intake and cancer resistance.

Paolo Boffetta, MD, MPH, lead author of the study and Deputy Director of The Tisch Cancer Institute at Mount Sinai School of Medicine, and colleagues analyzed data from the EPIC study to evaluate relationships between cancer risk and intake of total fruit and vegetables combined.

The EPIC followers, which are ongoing and organized by professor Elio Riboli at Imperial College in London, included 142,605 men and 335,873 women surveyed between 1992 and 2000 from 10 Western European countries. Detailed information on their dietary habits and lifestyle differences was obtained. After 8.7 years of follow – up, more than 30,000 of the study's participants were diagnosed with cancer.

Dr. Boffetta and colleagues found a small but significant opposite relationship between high intake of fruits and vegetables and overall cancer risk. In this population, an increase of 200 grams a day of fruits and vegetables resulted in a reduction of about 3 percent of cancer risk. Vegetable consumption by itself also afforded a modest benefit but was restricted to women. Heavy drinkers who ate many fruits and vegetables had a somewhat reduced risk, but only for cancers caused by smoking and alcohol.

"The bottom line here is that, yes, we did find a protective effect of fruit and vegetable intake against cancer, but it is a smaller connection than previously thought," said Dr. Boffetta. "Any cancer protective effect of these foods is likely to be modest, at best.

"However, eating fruits and vegetables is beneficial for health in general and the results of this study do not justify changing current recommendations aiming at increasing intake of these foods," said Dr. Boffetta.

63．A new study shows that         .

A．eating fruits and vegetables is beneficial to health

B．a diet rich in fruits and vegetables can reduce the risk of cancer

C．eating five servings of fruits and vegetables a day can prevent cancer and other diseases

D．the association between fruit and vegetable intake and cancer resistance is small

64．Before this study, people would believe that        .

A．high intake of fruits and vegetables can prevent cancer and other diseases

B．heavy drinkers have the slightest chance of cancer

C．the WHO’s recommendations were modest

D．the WHO’s recommendations aim at increasing intake of fruits and vegetables

65．The population who took part in this study amounted to       .

A．142,605    B．335,873    C．more than 400,000   D．30,000

66．From this study, we can infer that         .

A．the intake of fruits and vegetables will be no longer necessary

B．the connection between fruits and vegetables intakes and cancer resistance is smaller than originally thought

C．taking in fruits and vegetables will still be appreciated in spite of the new discovery

D．any cancer protective effect of these foods is likely to be modest

蝇类的寿命有多长？

下边沿至楼板或底面低于80㎝的窗台等竖向的洞口，如另一边落差大于3m，应加设12m高的临时护栏。（）