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When we accept the evidence of our unaided eyes and describe the Sun as a yellow star, we have summed up the most important single fact about it at this moment in time. It appears probable, however, that sunlight will be the color we know for only a negligibly small part of the Sun’s history. Stars, like individuals, age and change. As we look out into space, we see around us stars at all stages of evolution. There are faint bloodred dwarfs so cool that their surface temperature is a mere 4,000 degrees Fahrenheit, there are searing ghosts blazing at 100,000 degrees Fahrenheit and almost too hot to be seen, for the great part of their radiation is in the invisible ultraviolet range. Obviously, the "daylight" produced by any star depends on its temperature; today (and for ages to come) our Sun is at about 10,000 degrees Fahrenheit, and this means that most of the Sun’s light is concentrated in the yellow band of the spectrum, falling slowly in intensity toward both the longer and shorter light waves. That yellow "hump" will shift as the Sun evolves, and the light of day will change accordingly. It is natural to assume that as the Sun grows older, and uses up its hydrogen fuel—which it is now doing at the spanking rate of half a billion tons a second—it will become steadily colder and redder. The passage indicates that the change of the Sun’s yellow color is related with ______.
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It is difficult to imagine what life would be like without memory. The meanings of thousands of everyday perceptions, the bases for the decisions we make, and the roots of our habits and skills are to be found in our past experiences, which are brought into the present by memory. Memory can be defined as the capacity to keep information available for later use. It includes not only "remembering" things like arithmetic or historical facts, but also involves any change in the way an animal typically behaves. Memory is involved when a rat gives up an eating grain because he has sniffed something suspicious in the grain pile. Memory is also involved when a six-year-old child learns to swing a baseball bat. Memory exists not only in humans and animals but also in some physical objects and machines. Computer, for example, contains devices for storing data for later use. It is interesting to compare the memory storage capacity of a computer with that of a human being. The instant-access memory of a large computer may hold up to 1,000,000 "words" ready for instant use. An average U.S. teenager probably recognizes the meaning of about 100,000 words of English. However, his is but a fraction of the total amount of information which the teenager has stored. Consider, for example, the number of faces and places that the teenager can recognize on sight. The use of words is the basis of the advanced problem solving intelligence of human beings. A large part of a person’s memory is in terms of words and combinations of words. The phrase "in terms of" in the last sentence can best be replaced by ______.
In recent years, Israeli consumers have grown more demanding as they’ve become wealthier and more worldly wise. Foreign travel is a national passion, this summer alone, one in 10 citizens will go abroad. Exposed to higher standards of service elsewhere, Israelis are returning home expecting the same. American firms have also begun arriving in large numbers. Chains such as KFC, McDonald’s and Pizza Hut are setting a new standard of customer service, using strict employee training and constant monitoring to ensure the friendliness of frontline staff. Even the American habit of telling departing customers to "Have a nice day" has caught on all over Israel. "Nobody wakes up in the morning and says, ’Let’s be nicer,’" says Itsik Cohen, director of a consulting firm. "Nothing happens without competition." Privatization, or the threat of it, is a motivation as well. Monopolies (垄断者) that until recently have been free to take their customers for granted now fear what Michael Perry, a marketing professor, calls "the revengeful (报复的) consumer". When the government opened up competition with Bezaq, the phone company, its international branch lost 40% of its market share, even while offering competitive rates. Says Perry, "People wanted revenge for all the years of bad service." The electric company, whose monopoly may be short-lived, has suddenly stopped requiring users to wait half a day for a repairman. Now, appointments are scheduled to the half-hour. The graceless E1A1 Airlines, which is already at auction (拍卖), has returned its employees to emphasize service and is boasting about the results in an ad campaign with the slogan, "You can feel the change in the air." For the first time, praise outnumbers complaints on customer survey sheets. Why did Bezaq’s international branch lose 40% of its market share
He was a funny looking man with a cheerful face, good natured and a great talker. He was described by his student, the great philosopher Plato, as "the best and most just and wisest man". Yet this same man was condemned (判刑) to death for his beliefs. The man was the Greek philosopher, Socrates, and he was condemned for not believing in the recognized gods and for corrupting young people. The second charge stemmed from his association with numerous young men who came to Athens from all over the civilized world to study under him. Socrates’ method of teaching was to ask questions and, by pretending not to know the answers, to press his students into thinking for themselves. His teachings had unsurpassed influence on all the great Greek and Roman schools of philosophy. Yet, despite his fame and influence, Socrates himself never wrote a word. Socrates encouraged new ideas and free thinking in the young, and this was frightening to the conservative people. They wanted him silenced. Yet, many were probably surprised that he accepted death so readily. Socrates had the right to ask for a lesser penalty, and he probably could have won over enough of the people who had previously condemned him. But Socrates, as a firm believer in law, reasoned that it was proper to submit to the death sentence. So he calmly accepted his fate and drank a cup of poison in the presence of his grief-stricken friends and students. The word "unsurpassed" in the third paragraph is closest in meaning to ______.
In recent years, Israeli consumers have grown more demanding as they’ve become wealthier and more worldly wise. Foreign travel is a national passion, this summer alone, one in 10 citizens will go abroad. Exposed to higher standards of service elsewhere, Israelis are returning home expecting the same. American firms have also begun arriving in large numbers. Chains such as KFC, McDonald’s and Pizza Hut are setting a new standard of customer service, using strict employee training and constant monitoring to ensure the friendliness of frontline staff. Even the American habit of telling departing customers to "Have a nice day" has caught on all over Israel. "Nobody wakes up in the morning and says, ’Let’s be nicer,’" says Itsik Cohen, director of a consulting firm. "Nothing happens without competition." Privatization, or the threat of it, is a motivation as well. Monopolies (垄断者) that until recently have been free to take their customers for granted now fear what Michael Perry, a marketing professor, calls "the revengeful (报复的) consumer". When the government opened up competition with Bezaq, the phone company, its international branch lost 40% of its market share, even while offering competitive rates. Says Perry, "People wanted revenge for all the years of bad service." The electric company, whose monopoly may be short-lived, has suddenly stopped requiring users to wait half a day for a repairman. Now, appointments are scheduled to the half-hour. The graceless E1A1 Airlines, which is already at auction (拍卖), has returned its employees to emphasize service and is boasting about the results in an ad campaign with the slogan, "You can feel the change in the air." For the first time, praise outnumbers complaints on customer survey sheets. The example of E1A1 Airlines shows that ______.
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