单项选择题

【案例分析题】
Humanity uses a little less than half the water available worldwide.Yet occurrences of shortages and droughts （干旱）are causing famine and distress in some areas，and industrial and agricultural by-products are polluting water supplies.Since the world’s population is expected to double in the next 50years，many experts think we are on the edge of a widespread water crisis.
But that doesn’t have to be the outcome.Water shortages do not have to trouble the world--if we start valuing water more than we have in the past.Just as we ’began to appreciate petroleum more after the 1970s oil crises，today we must start looking at water from a fresh economic perspective.We can no longer afford to consider water a virtually free resource of which we can use as much as we like in any way we want.
Instead，for all uses except the domestic demand of the poor，governments should price water to reflect its actual value.This means charging a fee for the water itself as well as for the supply costs.
Governments should also protect this resource by providing water in more economically and environmentally sound ways.For example，often the cheapest way to provide irrigation （灌溉）water in the dry tropics is through small-scale projects，such as gathering rainfall in depressions （凹地）and pumping it to nearby cropland.
No matter what steps governments take to provide water more efficiently，they must change their institutional and legal approaches to water use.Rather than spread control among hundreds or even thousands of local，regional，and national agencies that watch various aspects of water use，countries should set up central authorities to coordinate water policy.
What is the real cause of the potential water crisis?（）

A．Only half of the world's water can be used.
B．The world population is increasing faster and faster.
C．Half of the world's water resources have been seriously polluted.
D．Humanity has not placed efficient value on water resources.

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单项选择题

产业经济学属于应用经济学。( )

A.正确
B．错误

单项选择题

【案例分析题】
Children’s Numerical Skills
People appear to be born to compute.The numerical skills of children develop so early and so inexorably that it is easy to imagine an internal clock of mathematical maturity guiding their growth.Not long after learning to walk and talk，they can set the table with impressive accuracy—one knife，one spoon，one fork，for each of the five chairs.Soon they are capable of noting that they have placed five knives，spoons and forks on the table and，a bit later，that this amounts to fifteen pieces of silverware.Having thus mastered addition，they move on to subtraction.It seems almost reasonable to expect that if a child were secluded on a desert island at birth and retrieved seven years later，he or she could enter a second-grade mathematics class without any serious problems of intellectual adjustment.
Of course，the truth is not so simple.This century，the work of cognitive psychologists has illuminated the subtle forms of daily learning on which intellectual progress depends.Children were observed as they slowly grasped—or，as the case might be，bumped into—concepts that adults take for granted，as they refused，for instance，to concede that quantity is unchanged as water pours from a short stout glass into a tall thin one.Psychologists have since demonstrated that young children，asked to count the pencils in a pile，readily report the number of blue or red pencils，but must be coaxed into finding the total.Such studies have suggested that the rudiments of mathematics are mastered gradually，and with effort.They have also suggested that the very concept of abstract numbers—the idea of a oneness，a two ness，a three ness that applies to any class of objects and is a prerequisite for doing anything more mathematically demanding than setting a table—is itself far from innate.
Children can set table even before they can walk and talk.（）

A．Right
B．Wrong
C．Not mentioned