题目

Could your cellphone give you cancer? Whether it could or not, some people are worrying about the possibility that phones, powerlines and wi-fi (路由器) could be responsible for a range of illnesses, from rashes to brain tumours. For example, Camilla Rees, 48, a former investment banker in the US, moved out of her apartment in San Francisco because of the radiation coming from next door. Rees told the Los Angeles Times that when her neighbors moved in and installed a wi-fi router she lost her ability to think clearly. “I would wake up dizzy in the morning. I’d fall to the floor. I had t17．将金属块挂在弹簧测力计下端，先后浸没在水和酒精中，金属块静止时弹簧测力计的示数如图中甲、乙所示．则金属块在水中受到的浮力为1N，金属块密度为3×103kg/m3．（ρ酒精=0.8×103kg/m3，g取10N/kg ）