Scientists have devised a way to determine roughly where a person has lived using a strand of hair, a technique that could help track the movements of criminal suspects or unidentified murder victims. The method relies on measuring how chemical variations in drinking water show up in people's hair. "You're what you eat and drink, and that's recorded in your hair," said Thure Cerling, a geologist at the University of Utah. While U.S diet is relatively identical, water supplies vary. The differences result from weather patterns. The chemical composition of rainfall changes slightly as rain clouds move. Most hydrogen and oxygen atoms in water are stable, but traces of both elements are also present as heavier isotopes . The heaviest rain falls first. As a result, storms that form over the Pacific deliver heavier water to California than to Utah. Similar patterns exist throughout the U.S. By measuring the proportion of heavier hydrogen and oxygen isotopes along a strand of hair, scientists can construct a geographic timeline. Each inch of hair corresponds to about two months. Cerling's team collected tap water samples from 600 cities and constructed a map of the regional differences. They checked the accuracy of the map by testing 200 hair samples collected from 65 barber shops. They were able to accurately place the hair samples in broad regions roughly corresponding to the movement of rain systems. "It's not good for pinpointing ," Cerling said. "It's good for eliminating many possibilities." Todd Park, a local detective, said the method has helped him learn more about an unidentified woman whose skeleton was found near Great Salt Lake. The woman was 5 feet tall. Police recovered 26 bones, a T-shirt and several strands of hair. When Park heard about the research, he gave the hair samples to the researchers. Chemical testing showed that over the two years before her death, she moved about every two months. She stayed in the Northwest, although the test could not be more specific than somewhere between eastern... What is the practical value of Cerling's research? A) It helps analyze the quality of water in different regions. B) It helps the police determine where a crime is committed. C) It helps the police narrow down possibilities in detective work. D) It helps identify the drinking habits of the person under investigation.
C
While I was waiting to enter university,I saw advertised in a local newspaper a teaching post at a school in a suburb of London about ten miles from where I lived. Being very short of money, I applied. Three days later, a letter arrived, asking me to go to Croydon for an interview. It proved a tiring journey: a train to Croydon station; a ten-minute bus ride and then a walk of at least fifteen minutes. It was clearly the headmaster himself that opened the door. He was short and fat, with a grey-color1ed moustache,a deeply lined face and hardly any hair. He looked at me with surprised disapproval. Then he said. "You'd better come inside." Leading me into his study, he started to ask me a number of questions: what subjects I had taken in my General School Certificate;how old I was; what games I played; whether I thought games were an important part of a boy's education, etc. I said something about not attaching too much importance to them. We obviously had very little in common. The teaching arrangement filled me with fear. I was to divide the class of twenty-four boys, aged from seven to thirteen, into three groups and teach them all subjects--including art, football, cricket and so on--in turn at three different levels. Actually, I was depressed at the thought of teaching algebra and geometry--two subjects in which I had been rather weak at school. I said shyly, "What would my salary be?" "Twelve pounds a week plus lunch." Before I could speak, he got to his feet. "Now," he said, "you'd better meet my wife. She's the one who really runs this school." This was the last thing I could hear. I was young. How could my dignity allow me to work under an old woman? What was the man's first attitude towards the writer? A) Pleased approval. B) Scared doubt. C) Amazed disapproval. D) Excited pleasure
C
Q: The uninvolved dad, turning up his nose at diapering and too busy to bathe, dress and play with his kids, is mostly a myth , a big government survey suggests. Most American fathers say they are heavily involved in hands-on parenting, the researchers found. The results are encouraging and important " because others have found the more involved dads are, the better the outcomes for their children. " said researcher Jo Jones of the National Center for Health Statistics, part of the Centers for Disease Control Prevention. She co-authored the report released Friday. "Times have changed," said Robert Loftus, 34, of Yonkers, NY. He quit a six-figure sales job a year ago to care for his two young children while his wife works full time. "We are trying to rethink our priorities and family seem to be N0 1 priority while in the past maybe people were more focused on career. " The study involved nearly 4.000 fathers who were interviewed in person between 2009 and 2013. *Key findings among fathers living with children younger than 5 : *9 in 10 bathed, diapered, helped them use the toilet or get dressed at least several times weekly . * Even higher numbers played with them and ate meals with them that often * Almost 2 0ut of 3 read to them at least several times weekly. *Among dads living with kids aged 5-18. * More than 9 0ut of 10 ate meals with them at least several times weekly and talked with them about what happened during the kids' day that often. * Almost 2 0ut of 3 helped with homework several times weekly. * About half took their kids to or from activities that often. Dr. David Hill, a Wilmington, N. C. pediatrician said the survey reflects what he's seen among his patients' fathers. Increasingly, fathers rather than mothers take their kids to the doctor. Some "are anxious about changing a diaper, " he said. Census numbers show that there were almost 190,000 stay-at-home dads nationwide last year versus 93,000 in 2010. Loftus, the New York stay-at-home dad, said, "I feel fortunate to be able... Which of the following can be the best title for the text? A) More stay-at-home dads in America B) Parents spend more time with children . C) The importance of family for Americans D) American dads more involved in parenting
A: D
(Question)
Most families love home cooking! The food tastes good and warm, and a family meal brings everyone together.In some families, meals are often the only times everyone sees one another the same time. Another reason people enjoy home cooking is that it is often a way of showing love.A parent who makes some cookies is not just satisfying a child's sweet tooth. She or he is sending a message.The message says, "I care about you enough to spend an hour making cooking that you will eat up in 15 minutes if I let you." There is also something about the smell of home cooking.The smell of home cooking pleases people of all ages.It makes most of us feel good and loved----- even if we are the ones doing the cooking! Next time you smell a cake making, stop for a moment and pay attention to your mood . The writer writes this passage to tell us _ . A) family meals are important. B) how to make cookies. C) people are too busy to cook. D) homemade cookies taste better.
(Answer)
A