Q=uS或G=Qρ=uSρ为流量方程。

Since we are social beings, the quality of our lives depends in large measure on our interpersonal relationships. One strength of the human condition is our tendency to give and receive support from one another under stressful circumstances. Social support consists of the exchange of resources among people based on their interpersonal ties. Those of us with strong support systems appear better able to cope with major life changes and daily hassles. People with strong social ties live longer and have better health than those without such ties. Studies over a range of illnesses, from depression to heart disease, reveal that the presence of social support helps people fend off illness, and the absence of such support makes poor health more likely.
Social support cushions stress in a number of ways. First, friends, relatives, and co-workers may let us know that they value us. Our self-respect is strengthened when we feel accepted by others despite our faults and difficulties. Second, other people often provide us with informational support. They help us to define and understand our problems and find solutions to them. Third, we typically find social companionship supportive. Engaging in leisure-time activities with others helps us to meet our social needs while at the same time distracting us from our worries and troubles. Finally, other people may give us instrumental support—financial aid, material resources, and needed services—that reduces stress by helping us resolve and cope with our problems.
Social companionship is beneficial in that______.

A:it helps strengthen our ties with relatives B:it enables us to eliminate our faults and mistakes C:it makes our leisure-time activities more enjoyable D:it draws our attention away from our worries and troubles

Whether it will do us harm remains ______.

A:seen B:seeing C:being seen D:to be seen

The author means to tell us that ______.

A:a man's place is in the home B:a woman' s place is in the home C:a woman should be equal to a man D:a man should have an equal share in family matters

Rarely do major diseases have a single cause. They are usually the result of a complex interaction between many factors, including genetic, environmental and lifestyle components. Many media reports, however, can tead us to believe that if we gave up something that we might otherwise enjoy, we could completely escape that particular affliction.
Clearly, this is not the case. Vegetarians die of cancer of the colon (结肠). Teetotallers die of liver complaints, including cirrhosis (硬化). People who never go out in the sun contract skin melanomas (黑素瘤). Always, there are other factors at work than the single element being examined in a scientific study.
Quite often the alleged benefits of a particular nutritional element are the result not so much of the element itself but of the lifestyle and general diet of the people who consume it most. People who eat lots of "healthy" foods, including fiber, carrots, broccoli etc. , also tend to drink less alcohol, take more exercise, avoid too many fatty foods and smoke less. Only when a study can rule out all of these other factors and often we do not know what these factors might be can we say that there is a causal link between two things. That is not to say that things like fiber and broccoli have no beneficial effects at all. But those with sedentary lifestyles cannot expect these foods to make them healthy.
There is, however, one thing which increases the likelihood of dying relatively young, even when all of the other factors have been taken into account. It is one of the biggest killers even among those who lead lifestyles which, by any criteria, are clearly healthy ones. This single, incontrovertible risk factor is that of being poor. Recent report from the Cancer Research Campaign suggested that 12 700 deaths could have been avoided between 1986 and 1990 if inequalities in cancer care did not exist in England and Wales. Comparing cancer survival rates, the study found that England and Wales fared unfavorably with Europe and the US, but the most affluent regions of these two countries exhibited similar figures to the European average.
In an attempt to counter this disparity the government has announced plans for the provision of Health Action Zones which seek to encourage greater cooperation between health and social services, targeting both rural and inner city areas. The emphasis of this new scheme however appears to focus on inadequacies within health education in these areas, rather than attacking the broader issues of social inequality.

A:people in Wales eat more unhealthy food than people in the US B:people in Wales are poorer than people in the US C:people in Wales are richer than people in the US D:cancers in Wales are caused by more complex factors than those in the US

In this passage, the writer tells us ______.

A:the difference between children and adults B:the different stages of the development of children C:how to dress children D:the slow development of the mind of a child

There are signs ( ) they are cheating us.

A:that B:which C:where D:on which

It’ll be easier for us to ( ) to facts then.

A:get down B:get up C:get on D:get off

It’ll be easier for us to( )to facts then．

A:get down B:get up C:get on D:get off

某进口贸易公司从美国进口了一台电梯，发票列明如下：成交价格为CIF珠海USS100000，电梯进口后的安装、调试费US＄4000，经海关审查上述成交价格属实，且安装、调试费已包含在成交价格中，则海关审定该台电梯的完税价格为（）。

A:US＄100000 B:US＄104000 C:US＄96000 D:US＄98000