TEXT C
Although we Americans in recent decades have grown richer, our children have grown poorer. Many families no longer adequately perform the nurturing and supporting function that children need, emotionally and intellectually.
The evil consequences for children are not in dispute. The fate of suicide among children aged ten to fourteen is twice as high as it was twenty years ago.
For children aged fifteen to nineteen, the rate has tripled.
Since 1983, crimes by children have been rising at a faster rate than the juvenile population. About half of such crimes involve the traditional youthful offenses of theft, breaking and entering, and vandalism, but serious, violent crimes, though still involving a relatively small proportion of children, are going up at a startling rate. The rate of armed robbery, rape, and murder by juveniles has doubled in a decade.
The Senate Juvenile Delinquency Subcommittee surveyed 750 school districts and reported the following changes between 1990 and 1993. Dropouts increased by 11 percent. Drug and alcohol offenses on school property were up 37 percent. Burglaries of school buildings were up 11 percent and assaults on teachers up 77 percent.
Among those who are thought of as “normal” children, lower reading scores and scholastic aptitude scores reveal intellectual impoverishment. Beyond all this loom the apathy and waste of the counterculture. Its existence is no longer news, but its ranks are still swelled each year by thousands of pathetic runaways and dropouts.
What forces are producing the increasingly severe stresses on today’s children?
The phenomenon is complex and baffling, but several developments seem to be interacting. Urbanization is a factor. Children who might have made it on a farm or in a village, despite adverse family circumstances such as extreme poverty or a father’s desertion, encounter disaster in a big city with its anonymity and diverse temptations.
Births by unwed mothers and divorce, two trends that are both rising steadily, result in depriving children of the stable, two-parent support that they need in their growing years. One out of every six children under eighteen today is living in a single-parent family. This is almost double the proportion in 1950.
Many divorced or widowed parents obviously succeed with their children, but ideally, rearing a child is a two-person job. When one parent is missing, the risk of failure increases. Indeed, it is best if a child has grandparents or other supportive relatives on the scene as well.
Instead, what has happened is the near disappearance of the extended family and the substitution of television, the hopelessly inadequate electronic baby-sitter. One study, for example, revealed that fifty years ago half of the households in Massachusetts included at least one adult besides the parents. Today the figure is only 4 percent. In a. small child’s life, “ Captain Kangaroo” is no substitute for a devoted grandmother.
72. The damaging effect of the treatment many American children receive today____
A. has not been taken seriously
B. has aroused hot debates
C. is beginning to be recognized
D. is unquestionable
73. Which of the following is NOT implied in the article?
A. Divorced parents can never rear good children.
B. One sixth of the American children live in one-parent families.
C. Two-parent families have better chances of raising their children successfully.
D. Nowadays there are nearly twice as many single-parent families as there used to be in 1950.
74. “ Captain Kangaroo” can’t offer ____ to a child.
A. entertainment
B. companionship
C. love and care
D. education
TEXT D
The accuracy of scientific observations and calculations is always at the mercy of the scientist’s time keeping methods. For this reason, scientists are interested in devices that give promise of more precise timekeeping.
In their search for precision, scientist have turned to atomic clocks that depend on various vibrating atoms or molecules to supply their “ticking”. This is possible because each kind of atom or molecule has its own characteristic rate of vibration. The nitrogen atom in ammonia, for example, vibrates or “ticks” 24 billion times a second.
One such atomic clock is so accurate that it will probably lose no more than a second in 3000 years. It will be of great importance that in fields such as astronomical observation and long-range navigation. The heart of this Atomichron is a cesium atom that vibrates 9.2 billion times a second when heated to the temperature of boiling water.
An atomic clock that operates with an ammonia molecule may be used to check the accuracy of predictions based on Einstein’s relativity theories, according to which a clock in motion and a clock at rest should keep time differently. Placed in an orbiting satellite moving at a speed of 18,000 miles an hour, the clock could broadcast its time readings to a ground station, where they would be compared with the readings on a similar model. Whatever differences develop would be checked against the differences predicted.
75. From the selection, we may assume that temperature changes____.
A. affect only ammonia molecules.
B. may affect the vibration rate of atoms.
C. affect the speed at which the atoms travel.
D. do not affect atoms in any way.
76. Implied but not stated:____.
A. precise timekeeping is essential in science
B. scientists expect to disprove Einstein’s relativity theories
C. atomic clocks will be important in space flight
D. the rate of vibration of an atom never varies
77. An appropriate title for this selection would be ____.
A. A Peacetime Use of the Atom
B. Atoms and Molecules
C. The Satellite Timekeepers
D. The Role of the Clock