在大小相同的2个红球和2个白球中，若从中任意选取2个，则所选取的2个球中恰好有1个红球的概率为______．
在大小相同的2个红球和2个白球中，若从中任意选取2个，所有的取法共有
=6种，C 24
则所选取的2个球中恰好有1个红球的取法有
?C 12
=4种，C 12
故则所选取的2个球中恰好有1个红球的概率等于
=4 6
，2 3
故答案为
．2 3
阅读下面短文，并根据短文内容在在文章后表格中的空格里填入一个最恰当的单词。每空一词。 How important is music? When they are asked this question, students and parents usually answer that music is nice, but not very important. It is often considered only as entertainment, but not the first choice for education. This opinion is shortsighted. In fact, music education is necessary and important for all students. Music tells us who we are. Music reflects the creators’ thinking and values, as well as the social environment it came from. For example, just as Mozart music represents a lifestyle, rock music represents a lifestyle, too. The jazz influence that George Gershwin and other musicians introduced into their music is obviously American because it came from American musical traditions. Music provides a kind of ability to know the world in a different way. Science explains how the sun rises and sets. Music explores the emotive meanings. We need every possible way to discover and response to our world because no one way can get it all. Music is a form of thought, as powerful as science. It is a way we human beings “talk” to each other. Through the language we expresses our feelings, our discoveries, our ideas, our imagination and our hopes so that they can be shared with others. When we do not let our children receive good music education, we take away from them the meanings that music expresses. Science does not tell us what it means to be human. Music does. So music education is much more necessary than people generally realize. Title: Music education is of 小题1:
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