题干

⊙O的半径为2,点P是⊙O外一点,OP的长为3,那么以P为圆心,且与⊙O相切的圆的半径一定是(       )

A:1或5

B:1

C:5

D:1或4

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答案(点此获取答案解析)

A

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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。

    Everyone, from homeless people to billionaires, is likely to be influenced by stress; there's simply no way to avoid it ____ Here are five powerful tips for ways to kill stress in almost any situation.

Eat Healthier

    Though a lot of stress is psychological, there are also plenty of physical factors that lead to this natural human response to noticed danger, In order to relieve stress, make sure you're treating your body right. A big part of this is eating healthier ____ Anyway, adopting an alkaline(碱性的)diet instead of an acidic (酸性的)one is recommended.

Wake Up Earlier

    ____ However, waking up 15 or 20 minutes earlier each morning may have more benefits than sleeping in. By giving yourself some extra time, you won't feel quite rushed in the morning, which leads to better preparation and more confidence.

____

    Since you are never going to remove 100 percent of the stress in your life, one of the best things you can do is let it be one of your motivations. This is what stress is designed to do, after all. The psychological and physical reactions brought on by stress are supposed to heighten our senses and empower us to fight off a threat.

Watch a Funny Video

    Here is a simple and practical tip: watch a funny video on You Tube, Research shows that seeing something amusing activates the part of the brain that produces calm physiological(生理的)responses. This can lead to less anxiety and more happiness.

Take Walk Outside

    Whenever possible, make sure you take your walk outdoors ____ It can improve energy levels and memory by as much as 20 percent.

A.A number of studies are two important keys to good health.

B.Diet and relaxation are two important keys to good health.

C.There are no magic”anti-stress”foods.

D.However, there are ways to reduce the amount of stress you suffer from.

E.Keep Positive Relationships

F.Let Stress Motivate You

G.It is certainly true that the more sleep you get, the less stressed you'll be.