正常停车后，冷区倒空置换步骤中，最先进行的步骤是（）。A．导液 B．泄压 C．系统隔
题型：单项选择题
问题：
正常停车后，冷区倒空置换步骤中，最先进行的步骤是（）。
A．导液
B．泄压
C．系统隔离
D．氮气置换
题型：单项选择题
WARNING: Holding a cell phone against your ear or putting it in your pocket may be bad for your health.
This sentence is a warning that you’d better not put it close to you when a new phone is bought. Apple company, for example, doesn't want IPhones to come closer to you than 1.5 centimeters; Research In Motion, BlackBerry's producer, recommends 2.5 centimeters.
(1)If cell phone use can health problems, the will be very serious. Americans spend 2.26 trillion minutes chatting on cell phones every year, which brings $109 billion for the wireless businessmen.
Devra Davis, an epidemiologist(皮肤病专家) who has worked for the University of Pittsburgh, has published a book about mobile phone radiation（辐射）"Disconnect." Davis studies how often brain cancer happens during different age groups. She finds a big increase in brain cancer in the 20-to-29 age group and a drop for the older people.
Children are more easily hurt by radiation than grown-ups, Ms. Davis and other scientists point out. But no studies have yet been finished on cell phone radiation and children, she says.
Henry Lai, a research professor, began lab radiation studies in 1980 and found that mice exposed to(暴露在) radiofrequency（电波频率）radiation had destroyed DNA in their brains.
Ms. Davis recommends using wired earphones（有线耳机）or the phone's speaker. (2)Children should send text messages rather than call, she said, and pregnant（怀孕的） women should keep phones away from their bodies.
小题1:在（1）句空白处填入适当的词使句意完整、上下文通顺。
小题2:将（2）句翻译成中文。
小题3:回答问题：What kind of people with brain cancer are getting more and more?
小题4:找出同义句。
Scientists are still carrying on with the studies on cell phone radiation and children
小题5:找出或写出该短文的主题句。