连续抛掷两颗骰子，设第一颗点数为m，第二颗点数为n，则求：（_爱下问搜题

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问题解答题

连续抛掷两颗骰子，设第一颗点数为m，第二颗点数为n，则求：

（1）m+n=7的概率；（2）m=n的概率；（3）点P（m，n）在圆x²+y²=16内的概率．

答案

共有6×6=36个基本事件，

（1）记“m+n=7”为事件A，则A包含6个基本事件，，（1，6），（2，5），（3，4），（4，3），（5，2），（6，1）．

故P（A）=

6

36

=

1

6

；

（2）记“m=n”为事件B，则B包含6个基本事件，（1，1），（2，2），（3，3），（4，4），（5，5），（6，6），故P（B）=

6

36

=

1

6

；

（3）记“点P（m，n）在圆x²+y²=16内”为事件C，则C包含8个基本事件，（1，1），（1，2），（1，3），

（2，1）（2，2），（2，3），（3，1），（3，2）．故P（C）=

8

36

=

2

9

．

完形填空

阅读下面短文，并借助上下文和插图补充所缺信息，每个空只需填写一个形式正确、意义相符的英语单词。请将答案写在答题卡相应题目的答题位置上。

Sam is a farmer. He has a very big 小题1:. On the farm, he grows oranges, grapes and bananas. Many people come to 小题2: his farm. He is a successful young man and becomes very famous.

Several years ago, in 2003, he went back to his hometown after he finished high school. “What can I do?” he said to himself. Then he had 小题3:idea. “I’m 小题4:in farming. I can grow fruit!” He began to watch many programs about growing fruit 小题5:TV. He also read a lot of books about

it. Then he went to 小题6: on Mr. Smith’s farm for two years. He learned a lot there. In 2005, he started his own fruit farm. At that 小题7:, Sam’s farm was small. But now, his farm is much 小题8:.

His fruits are very good .He sends them to many big 小题9: in China, such as Shanghai, Beijing and Guangzhou. He also grows vegetables and raises 小题10:on his farm. Therefore, his family eats their own vegetables and chicken. They have a very healthy lifestyle.

单项选择题

为了能在列表框中利用Ctrl和Shift键进行多个列表项的选择，则应将列表框的Multiselect属性设置为______ 。

A．0

B．1

C．2

D．3