《诗经》中的《七月》描述农民无冬无夏地劳动，却“无衣无褐”；一些爱情诗，反映了青年男女在恋爱婚姻生活中的喜怒哀乐。这说明《诗经》

    Look at the light and beautiful snowflakes (雪花) falling. Ever wanted to hold them in your hands? They are always lost when they meet your hands.

    Well, this isn't just a problem for you. It was a problem for Wilson Bentley, too. In the 1870s, Wilson Bentley was just a teenager. His family lived in a small town in northeast America. Winters there were long and hard. Bentley's mother was once a school teacher. She taught him at home. Bentley didn't go to school until he was 14. He was a quiet boy, and loved reading his mother's books. But he was interested in his mother's microscope (显微镜). When the other boys were playing with balls, little Bentley was studying things like drops of water, flowers and snowflakes.     

    Bentley loved watching snowflakes. For the next two years, young Bentley spent many winter days in a cold room watching these ice crystals (晶体) under his microscope. The boy thought they were beautiful enough for him to start to draw pictures of them. But there were so many snowflakes that he couldn't draw them all.

    How could he keep their beauty all the time? Bentley thought of buying a camera.

    The boy and his mother asked his father to buy one. But, his father didn't agree. He thought the whole thing was a bad idea. He thought the only thing a farmer should do was farming.

    But finally Bentley did get a camera. For more than a year he tried to take pictures of snowflakes. On January 15, 1885, during a snowstorm, Bentley took the first ever photo of an ice crystal with his camera. “It was the greatest moment of my life,” Bentley said later.

    For 13 years, Bentley worked quietly and took thousands of photos of ice crystals. Later he became famous as “Snowflake” Bentley.

下列说法符合可持续发展观点的是（　　）

构造原理揭示的电子排布能级顺序，实质是各能级能量高低．若以E（nx）表示某能级的能量，以下各式中正确的是（　　）

①E（4s）＞E（3s）＞E（2s）＞E（1s）         

②E（3d）＞E（4s）＞E（3p）＞E（3s）

③E（5s）＞E（4f）＞E（4s）＞E（3d）         

④E（5s）＞E（4s）＞E（4f）＞E（3d）

    The poverty line is the minimum income that people need for an acceptable standard of living. People with incomes below the poverty line are considered poor. Economists study the causes of poverty in order to find solutions to the problem.

    As the general standard of living in the country rises, the poverty line does, too. Therefore, even with today's relatively high standard of living, about 10 percent of the people in the United States are below the poverty line. However, if these people had stable jobs, they could have an acceptable standard of living. Economists suggest several reasons why poor people do not have jobs.

    For one thing, more than half of the poor people in the United States are not qualified to work. Over 40 percent of the poor people are children. By law, children less than 16 years old cannot work in many industries. A large number of poor people are old. Many companies do not hire people over 65 years old, the normal retirement age.

    Some poor adults do not look for jobs for a variety of personal reasons: they are sick, they do not have any motivation, they have family problems, or they do not believe that they can find a job.

    Other poor people look for a job, but cannot find one. Many poor adults never went to high school. Therefore, when they look for jobs, they have few skills that they can offer.

    At the present time, the government thinks it can reduce poverty in the country in the following ways:

    First, if the national economy grows, businesses and industries hire more workers. Some of the poor who are qualified to look for jobs may find employment. Then they will no longer below the poverty line.

    Second, if society invests in the poor，the poor will become more productive.

    If the government spends money on social programs, education and training for poor people, the poor will have the skills to offer. Then it is more probable that they can find jobs.

    Finally, if the government distributes society's income differently, it raises some poor people above the poverty line. The government collects taxes from the non-poor and gives money to the poor. These payments to the poor are called welfare.

    Some economists are looking for better solutions to the poverty problem. However, at the present time, many people depend on welfare for a minimally acceptable standard of living.