Holding a cell phone against your ear or stalling it in your pocket may be hazardous to yo

Holding a cell phone against your ear or stalling it in your pocket may be hazardous to your health．
This paraphrases a warning that cell phone; manufacturers include in the small print that is often tossed aside when a new phone is purchased．Apple, for example, doesn’t want iP hones to e closer to you than 1．5 centimeters; Research In Motion, Blackberry’s manufacturer, remends 2.5 centimeters．
If health issues arise from cell phone use, the implications are huge．Voice calls - Americans chat on cell phones 2．26 trillion minutes annually - generate $109 billion for the wireless carriers．
Devra Davis, an epidemiologist who has worked for the University of Pittsburgh, has published a book about cell phone radiation, Disconnect. The book surveys scientific research and concludes the question is not settled.
　　Brain cancer is a concern that Ms. Davis examines. Over all, there has not been an increase in its incidence since cell phones arrived. But the average masks an increase in brain cancer in the 20-to-29 age group and a drop for the older population.
　　Most cancers have multiple causes, she says, but she points to laboratory research that suggests low-energy radiation could damage cells that could possibly lead to cancer.
　　Children are more vulnerable to radiation than adults, Ms. Davis and other scientists point out. Radiation that penetrates only five centimeters into the brain of an adult will reach much deeper into the brains of children because their skulls are thinner and their brains contain more absorptive fluid. No studies have yet been pleted on cell phone radiation and children, she says.
　　Henry Lai, a research professor in the bioengineering department at the University of Washington, began laboratory radiation studies in 1980 and found that rats exposed to radiofrequency radiation had damaged DNA in their brains.
　　Ms. Davis remends using wired headsets or the phone’s speaker. Children should text rather than call, she said, and pregnant women should keep phones away from the abdomen.
【小题1】We can infer from the passage that    ．A．Cell phone may do harm to our health if we hold it against our ear or store in our pocketB．Devra Davis thinks that there are many factors contributing to cancer．C．The increase in brain cancer in the young adults may have something to do with cell phoneD．Children are more likely to be affected by radiation【小题2】According to the passage, how could children avoid being hurt by cell phone radiation?A．They can keep cell phones away from the abdomen．B．They can send short massage instead of making phone calls directly．C．They can pay more attention to the small print on the phone．D．They should use more advanced cell phones．【小题3】From this passage we can learn that．    ．A．American cell phone manufacturers did not give any warning to their customersB．American cell phone manufacturers benefit greatly from their productsC．Scientists have found the connection between brain cancer and ceil phoneD．Cell phone should be banned because of the increase in brain cancer【小题4】In which column can we most probably read this passage?A．Advanced technology．B．Entertainment．C．Science and life．D．Celebrity．C