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Vision Human vision like that of other primates(灵长类) has evolved in an arboreal(丛林) environment. (46) In the course of evolution, members of the primate line have acquired large eyes while the nose has shrunk. (47) Of mammals(哺乳动物) only humans and some primates enjoy color vision. (48) Horses live in a single-color world. Light visible to human eyes, however, occupies only a very narrow band in the whole electromagnetic spectrum(光谱). Ultraviolet rays(紫外线) are invisible to humans though ants and honeybees are sensitive to them. (49) The world would look terribly different if human eyes were sensitive to infrared radiation(红外线). Then instead of the darkness of night, we would be able to move easily in a strange shadowless world. (50) The color sensitivity of normal human vision is rarely surpassed even by complicated technical devices.A. Humans have no direct perception of infrared rays.B. In the dense complex world of a tropical forest, it is more important to see well than to develop an acute sense of smell.C. That gives the eye a wilder view.D. The red flag is black to the bull.E. There are different mammals in tropical forest.F. In this world, objects glowed with varying degrees of intensity.

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[函数2.1说明] 函数int strcmp(char s，char t)的功能是比较两个字符串s和t的大小。若s＜t，函数返回负数; 若s=t，函数返回0; 若s＞t，函数返回整数。 [函数2.1] int strcmp(char s,char t) while(s ＆＆ t ＆＆ (1) ) s++; t++; return (2) ; [函数2.2说明] 在n行n列的矩阵中，每行都有最大的数，求这n个最大数中最小的一个。 [函数2.2] #include ＜stdio.h＞ #define N 100 int a[N] [N]; void main() int row,col,max,min,n; scanf("%d"，＆n); for(row=0; row＜n; row++) for(col=0; col＜n; col++) scanf("%d",＆a[row] [col]); for (row=0; row＜n; row++) for (max=a[row][0],col=1; col＜ri; col++) if( (3) )max=a [row][col]; if( (4) ) min=max; else if( (5) ) min=max; printf("The main of max number is %d\n",min);

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Parents are encouraged to ______.(要多用说服的方法而不是惩罚的手段) to educate their children.

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Across the English Channel To swim across the English Channel takes at least nine hours. It’s a hard work and it makes you short of breath. To fly over the Channel takes only twenty minutes (as only as you’re not held up at the airport), but it’s an expensive way to travel. You can travel by hovercraft if you don’t mind the noise, and that takes forty minutes. Otherwise you can go by boat, if you dreams of being able to drive to France in his own car. "Not possible", you say. Well wait a minute. People are once again considering the idea of a Channel tunnel or bridge. This time, the Greater London Council is looking into the possibility of building a Channel link straight to London. A bridge would cost far more than a tunnel, but you would be able to go by rail or by car on a bridge, whereas a tunnel would provide a rail link only. Why is this idea being discussed again Is Britain becoming more conscious of the need for links with Europe as a result of joining the EEC (欧共体) Well, perhaps. The main reason, though, is that a tunnel or bridge would reach the twenty square kilometers of London’s disused dockland(船坞地). A link from London to the continent would stimulate trade and re-vitalize(使…重新具有活力)the port, and would make London a main trading center in Europe. With a link over the Channel, you could buy your fish and chips in England and be able to eat them in France while they were still warm! A tunnel would be ______.

A. less expensive to be built than a bridge
B. more expensive to be built than a bridge
C. less expensive to be built than a rail
D. more expensive to be built than a rail

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旅行社要遵守商业道德，在经营活动中要遵循、、、的原则。

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Parents are encouraged to ______.(要多用说服的方法而不是惩罚的手段) to educate their children.

旅行社要遵守商业道德，在经营活动中要遵循______、______、______、______的原则。

旅行社要遵守商业道德，在经营活动中要遵循、、、的原则。