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Mobile Phones
Mobile phones should carry a label if they proved to be a dangerous source of radiation, according to Robert Bell, a scientist. And no more mobile phone transmitter towers should be build until the long-term health effects of the electromagnetic (电磁的) radiation they emit is scientifically evaluated, he said. "Nobody’s going to drop dead overnight but we should be asking for more scientific information," Robert Bell said at a conference on the health effects of low-level radiation.
(46) A report widely circulated (传播) among the public says that up to now scientists do not really know enough to guarantee there are no ill effects on humans from electromagnetic radiation. According to Robert Bell, there are 3.3 million mobile phones in Australia alone and they are increasing by 32, 000 a day.
(47) As well, there are 2, 000 transmitter towers around Australia, many in high density (密度) residential area
[单项选择] Mobile phones
What Are Mobile Phones
A mobile phone, also known as a cellphone or cellular phone, is a portable electronic device which behaves as a normal telephone whilst being able to move over a wide area (compare cordless phone which acts as a telephone only within a limited range). Cellphones allow connections to be made to the telephone network, normally by directly dialing the other party’’s number on an inbuilt keypad. Most current cellphones use a combination of radio wave transmission and conventional telephone circuit switching, though packet switching is already in use for some parts of the cellphone network, especially for services such as Internet access and WAP.
Some of the world’’s largest cellphone manufacturers include Alcatel, Audiovox, Kyocera (formerly the handset division of Qualcomm), LG, Motorola, Nokia, Panasonic (Matsushita Electric), Philips, Sagem, Samsung, Sanyo, Siemens, SK Teletech, and Sony Ericsson.
A. Y
B. N
C. NG