长方形、正方形、平行四边形的共同特点是（ ） A．对边相等 B．有4个直角 C．四条边

下列关于招标采购的说法正确的是( )。

A．招标只能用于购买

B．招标完全等同于采购

C．采购标的物均是有形的

D．公开招标与邀请招标的区别之一在于是否邀请特定的法人或其他组织投标

我国疆域辽阔，各地地理环境差异显著，可分为四大地理区域，划分的主要依据是

A．年降水量的分布

B．季风区和非季风区的分界线

C．各地地理位置、自然和人文地理特点

D．一月份0℃等温线

阅读理解。

     A new study has found no evidence that sunscreen, commonly used to reduce the risk of skin cancer,

actually increases the risk.

     Researchers from the University of lows based their findings on a review of 18 earlier studies that looked

at the association between sunscreen use and melanoma (黑素瘤). They said that they found flaws in studies

that had reported associations between sunscreen use and higher risk of melanoma.

     Most health experts believe that by protecting the skin from the harmful effects of the sun, sunscreen

helps prevent skin cancer, which is increasing in incidence (发生率) faster than any other cancer in the

United States.

     But questions have been raised about sunscreen and whether it may have the opposite effect, perhaps

by allowing people to remain exposed to the sun longer without burning.

     The researchers said that among the problems with some earlier studies is that they often failed to take

into account that those people most at risk for skin cancer-people with fair skin and freckles (雀斑), for

example-are more likely to use sunscreen. As a result, it may appear that sunscreen users get cancer more

often.

     The studies, which generally relied on volunteers to recall their sunscreen use, were also unable to prove

how well the products had been applied, said the new study.

1. The underlined word "flaws" in the 2^nd paragraph most probably means _____.

A. evidences

B. facts

C. faults

D. failures

2. People with fair skin and freckles _____.

A. seldom use sunscreen

B. are more in danger of skin cancer

C. can be free from the harm of the sun

D. often expose themselves to the sun

3. We can learn from the passage that _____.

A. sunscreen users get skin cancer more often

B. the volunteers have proved the effect of sunscreen

C. the new study was based on the experiences of volunteers

D. the number of skin cancer patients is increasing in America

4. Which of the following can be the beat title for this passage?

A. Sunscreen to Prevent Skin Cancer

B. Sunscreen to Increase Skin Cancer

C. Skin Cancer Caused by Sunscreen

D. Skin Cancer Caused by Freckles

以下函数按每行8个输出数组中的数据：
void fun(int*w, int n)
int i;
for(i=0; i＜n; i++)
______
printf("%d", w[i]);

printf("\n");

下划线处应填入的语句是

A) if(i/8==0)printf("\n"); B) if(i/8==0)continue;
C) if(i%8==O)printf("\n"); D) if(i%8==0)continue;

根据保险法的基本原则，保险的投保人必须( )。

A．是保险合同中的受益人

B．是保险合同中的被保险人

C．对保险标的具有保险利益

D．是被保险人的亲属