A Bad Idea 　　
Think you can walk, drive, take phone calls, e-mail and listen to music at the same time Well, New York’s new law says you can’t._______(46) The law went into force last month, following research and a shocking number of accidents that involved people using electronic gadgets (小巧机械) when crossing the street. 　　
Who’s to blame _______ (47) "We are under the impression that our brain can do more than it often can," says Rene Marois, a neuroscientist (神经科学家) in Tennessee. "But a core limitation is the inability to concentrate on two things at once." 　　
The young people are often considered the great multi-taskers. _______ (48) A group of 18- to 21-year-olds and a group of 35- to 39-year-olds were given 90 seconds to translate images into numbers, using a sample code. _______ (49) But when both groups were interrupted by a phone call or an instant message, the older group matched the younger group in speed and accuracy. 　　
It is difficult to measure the productivity lost by multi-taskers. But it is probably a lot Jonathan Spira, chief analyst at Basex, a business-research firm, estimates the cost of interruptions to the American economy at nearly $650 billion a year. _______ (50) The surveys conclude that 28 percent of the workers’ time was spent on interruptions and recovery time before they returned to their main tasks.

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