题目内容
如下所示是一棵5阶B树，从该B树中删除关键码41后，该B树的叶结点数为
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有如下程序： #include＜iostream＞ using namespace std； class Base{ int x； public： Base(int n＝0):x(n){cout＜＜n;) int getX()const{return x;} }； class Derived:public Base{ int y； public： Derived(int m，int n):y(m,)Base(n){cout＜＜m;} Derived(int m):y(m){cout＜＜m;} }； int main(){ Derived d1(3),d2(5,7) return 0； }运行时的输出结果是
某产品划分为四个功能区，采用环比评分法得到的功能暂定重要性系数见下表。则功能区芦4的重要性系数为()。
A．other thanB．better thanC．rather thanD．no more than
Part A
Directions: Read the following four texts. Answer the questions below each text by choosing A, B, C or D. (40 points)
The energy crisis, which is being felt around the world, has dramatized how the careless use of the earth's resources has brought the whole world to the brink of disaster. Tile over development of motor transport, with its increase of more cars, more highways, more pollution, more suburbs, more commuting, has contributed to the near destruction of our cities, the breakup of the family, and the pollution not only of local air but also of the earth's atmosphere. The disaster has arrived in the form. of the energy crisis.
Our present situation is unlike war, revolution or depression. It is also unlike the great natural disasters of the past. Worldwide re sources exploitation and energy use have brought us to a state where long-range planning is essential. What we need is not a continuation of our present serious slate, which endangers the future of our country, our children, and our earth, but a movement forward to a new norm in order to work rapidly and effectively on planetary problems.
This country has been falling back under the continuing exposures of loss morality and the revelation that lawbreaking has reached into the highest places in the bad. There is a strong demand for moral revival and for some devotion that is vast enough and yet personal enough to enlist, the devotion of all. In the past 5t has been only in a way in defense of their own country and their own ideals that any people have been able to devote themselves wholeheartedly.
This is the first time that we have been asked to defend ourselves and what we hold dear in cooperation with all the other inhabitants of this planet who share with us the same endangered air and the same endangered oceans. There is a common need it reassesses our present course, to change that courser and to devise new methods through which the world can survive. This is a priceless opportunity.
To grasp item we need a widespread understanding of nature if the crisis confronting us—and the world—a crisis that is no passing in convenience, no by-product of the ambitions of the oil-producing countries, no environmentalists' mere fears, no by-product of any present system of government. What we face is the outcome of the invention of the last four hundred years. What we need is a transformed lifestyle. This new lifestyle. can flow directly from science and technology, but its acceptance depends on a sincere devotion to finding a higher quality of life for the world's children and future generation.
Which condition does the author feel has nearly destroyed our cities？
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