桌面上放有4张卡片，正面分别标有数字1，2，3，4，这些卡片除数_爱下问搜题

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问题解答题

桌面上放有4张卡片，正面分别标有数字1，2，3，4，这些卡片除数字外完全相同．把这些卡片反面朝上洗匀后放在桌面上，甲从中任意抽出一张，记下卡片上的数字后仍放反面朝上放回洗匀，乙从中任意抽出一张，记下卡片上的数字，然后将这两数相加．

（1）请用列表或画树状图的方法求两数和为5的概率；

（2）若甲与乙按上述方式作游戏，当两数之和为5时，甲胜；反之则乙胜；若甲胜一次得12分，那么乙胜一次得多少分，这个游戏对双方公平吗？

答案

（1）列表如下：

	1	2	3	4
1	（1，1）	（1，2）	（1，3）	（1，4）
2	（2，1）	（2，2）	（2，3）	（2，4）
3	（3，1）	（3，2）	（3，3）	（3，4）
4	（4，1）	（4，2）	（4，3）	（4，4）

（4分）

由列表可得：P（数字之和为5）=

1

4

（6分）

（2）因为P（甲胜）=

1

4

，P（乙胜）=

3

4

（8分），

∴甲胜一次得12分，要使这个游戏对双方公平，乙胜一次得分应为：12÷3=4分．（10分）

完形填空

One very cold and rainy night in the winter of 2012, my husband and I were in a fast food restaurant. We were about to begin our meal    a man walked in. He was completely       from the rain and went into the men's room.
I watched him go by, then I said to my husband, "That man must have had nothing to eat in a long time." When the man came out of the men's room, he just       himself in a chair, not going anywhere near the food counter. I       that he didn't have any money for food and       wanted to dry off for a while.
I just couldn't eat my food knowing that someone else was sitting      only a few tables away. So, I      a $20.00 bill from my shopping money to my husband. "Please get him dinner," I said. "We can do with less money this week."
My husband      the man and quietly asked if he needed some food. The man      at us. "A small cup of coffee would be great," he said. "Thank you so much!" He       wasn't going to take advantage of us, but we      that he should have a full meal, which he gratefully(感激地)       .
After he      the food, he thanked my husband and my husband said, "No. Thank my       . She noticed that you were       ."
The man asked me, "      did you know I haven't eaten in a long time?" I smiled at him and said nothing , just asking him to      the change(零钱) from the $20.00.
Giving others a      whenever they’re in trouble not only brings happiness to the ones who       it but also to the ones who give it. I am so grateful that I was able to      with someone truly in need. It is a little bit of extra warmth on a rainy day.

C．occasionally

D．immediately

A．in surprise

D．communicate

单项选择题

在《史记》一书中，较为全面描绘秦汉时期各地区域文化特色的是（）

A.《滑稽列传》

B.《秦始皇本纪》

C.《货殖列传》

D.《游侠列传》