题干

为践行低碳理念,家庭生活中常用LED灯取代白炽灯来照明,这是因为LED灯具有节能、____等优点(写出一点即可).一只“220V  22W”的LED灯正常工作时的电流是____A;若该灯正常发光时与一只“220V  100W”的白炽灯正常发光时亮度相当,则使用LED灯可节省____%的电能.
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环保(或寿命长等),0.1,78

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    If you're ever apart from your children, a new study says just talking on the phone will help just as much as a hug (拥抱).

    If you're a parent who spends long hours on the job, you probably feel sorry for spending so much time away from your kids. But the results of a new study show that a mother's voice alone can be just as comforting to an anxious child as physical contact (接触).

    In an experiment, researchers from the University of Wisconsin Madison asked a group of girls between the ages of 7 and 12 to solve math problems in front of judges — a stressful situation for anyone. Before the girls were set to give their answers, the researchers measured their levels of two hormones(荷尔蒙):cortisol,which goes up during stressful periods, and oxytocin, the “love” hormone, which goes down at the same time.

    After the girls finished the problems, some of them got to meet up with their mothers right away. The moms came in and hugged the girls. Another group of the girls didn't see their mothers, but received phone calls from them, in which their mothers told them how well they'd done. The final group had no contact with their mothers, but instead watched an animal movie, March of the Penguins.

    Finally, the girls' hormone levels were measured again. Although the movie was interesting, it did nothing to reduce the children's anxiety—but, surprisingly, both the physical contact and phone calls from their mothers had the same effect on reducing the girls' stress levels.

    So, no matter how old you are, if you're feeling stressed about something in your life, a phone call to Mom might be just the key to help you feel better.