题干

一个扇形的面积为12πcm2,圆心角为120°,则该扇形的半径是____.
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6cm

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根据短文内容,从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。

    Here, sleep experts clear up some of the biggest misunderstandings about sleep they see with their patients, which could weaken your ability to have a night of good sleep.

Myth: ____

    The latest research shows that the right amount of sleep may vary from person to person and should leave you feeling energized the next day. I'm a sleep doctor. Take myself for example. ____.

Myth: Don't fall asleep with the TV on.

    I've cured more people suffering from sleep problems than you can imagine by telling  people it's OK to fall asleep with the TV on. ____Control the watching time so it doesn't affect your sleep later in the night.

Myth: You can catch up on lost sleep on the weekend.

    ____ A Harvard study found that even if you sleep for an extra 10 hours on the weekend to make up for only sleeping six hours a night for two weeks, those extra hours won't improve  your reaction times or ability to focus. Plus, sleeping late throws off your biological clock, which can lead to obesity, diabetes, and heart disease.

Myth: Alcohol can help you rest easy.

    ____ Alcohol may relax you so you nod off quicker, but studies show you'll wake up more and get less of deep sleep you need to feel rested.

A. You need 8 hours' sleep a night.

B. A lack of sleep can cause anxiety.

C. We take unscheduled naps during the weekend.

D. I've been a 6.5-hour sleeper my entire adult life.

E. Many people can't turn off their brains, but watching TV helps.

F. People commonly use alcohol to fall asleep, but it doesn't work.

G. You can't make up for too little sleep by sleeping more at weekends.