题干

如图所示为两根互相平行的通电直导线a,b的横截面图,a,b中的电流方向已在图中标出,那么导线a中的电流产生的磁场的磁感线环绕方向及导线b所受的磁场力的方向分别是:     [          ]

A:磁感线顺时针方向,磁场力向左

B:磁感线顺时针方向,磁场力向右

C:磁感线逆时针方向,磁场力向左

D:磁感线逆时针方向,磁场力向右

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B

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阅读理解

    The story of the movie Inside Out mostly takes place inside the mind of 11-year-old Riley as she moves from Minnesota to San Francisco. The main characters are Riley's emotions---Joy, Sadness, Disgust, Anger and Fear, which guide her decisions and often compete with one another for control of her brain.

    Fear is tall, thin, looks like a frayed(焦燥的)nerve and is purple. Not only that, his eyes are purple, too. Anger, which is red, looks like a brick and has red eyes. Disgust, who is green, has green eyes. Sadness, not surprisingly, is completely blue, and even looks like a teardrop. But Joy, who is mainly yellow, has more than one color in her. She has blue eyes and blue hair. Why? Well, if blue represents sadness, then the message is clear: there is no such ting as “pure joy”. Instead, even in our most joyous times, there is often sadness mixed in.

    After all, one of the most joyous moments we can experience is a wedding, but it may end with the breaking of a glass. It reminds us that our world is still broken. In order words, even at our highest moments, there is always a little sadness.

    But the comfort is that the reverse is often true. Think about how you feel after crying. When you cry, your body is releasing some chemicals that often make you feel good. And that's why you feel at ease after a good cry.

    Indeed, Inside Out reminds us that even the emotions that appear “negative' have value. In other words, Inside Out shows us that the goal of life isn't “to be happy”. We will feel sad, angry or frightened. But we need our whole range of emotions for developing our sense of self and our relationship with others.