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【单选题】
【附加题】（请阅读课程团队微信号“AI之美”所提供的课外学习资料）有两种细菌x和y，需要根据细菌外形的（长，宽，高）对十个它们的样本进行区分，已知x细菌的5个样本的尺寸是（1，7，8），（1，8，9），（2，9，1），（4，1，1），（5，2，2），y细菌5个样本的尺寸是（3，3，3），（6，1，4），（7，4，5），（8，5，6），（9，6，7） ，假设我们用细菌外形的长度<5.5作为决策树分类的第一个分裂特征，那么这次分裂前后，样本集合的熵分别是多少？A.
0.5 ，0
B.
0.69,0.8
C.
0.69 ，0.45
D.
0.5 ，0.25
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举一反三
【简答题】数据的存储结构主要有四种,它们分别是____、____、____和____存储结构。
【单选题】在下图中,与查询设计器的筛选标签中所设置的筛选功能相同的表达式是( )。
A.
选修表.成绩>=80 AND 选修表.成绩=<90
B.
选修表.成绩>80 AND 选修表.成绩<90
C.
80<=选修表.成绩 <=90
D.
80
【单选题】图示有源二端电阻网络 A 外接电阻 R 为 12 W 时, I = 2 A ; R 短路时, I = 5 A 。 则当 R 为 24 W 时 I 为( )。
A.
4A
B.
2.5A
C.
1.25A
D.
1A
【简答题】设循环群 G 的阶是 p , 这里 p 为素数,则 G 有___个生成元
【简答题】观察与探究： 某礼堂共有25排座位，第一排有20个座位，后面每一排比前一排多1个座位，写出第25排的座位数．在以上其他条件不变的情况下，请探究下列问题 （1）当后面每一排都比前一排多2个座位时，写出第n排的座位数； （2）当后面每一排都比前一排多3个座位时，4个座位时，分别写出第n排的座位数； （3）某剧院共有P排座位，第一排有a个座位，后面每一排多b个座位，试写出第n排的座位数．
【单选题】（ 19 ）在下图中，与查询设计器的筛选标签中所设置的筛选功能相同的表达式是
A.
）成绩表 . 综合成绩 >=80AND 成绩表 . 综合成绩 =<90
B.
）成绩表 . 综合成绩 >80AND 成绩表 . 综合成绩 <90
C.
） 80<= 成绩表 . 综合成绩 <=90
D.
） 80< 成绩表 . 综合成绩 <90
【单选题】听力：What does the man say about Chinese?
A.
Q: What does the man say about Chinese? W: Hi, Leo. Why do you say English will become the world language? M: Well, for one thing, it's so commonly used. The only language that is used by more people is Chinese. W: Why is English spoken by so many people? M: It's spoken in many countries of the world because of the British Empire. And now, of course, there's influence of America as well. W: Many students find English a difficult language to learn. M: Oh, all languages are difficult to learn. But English does have two great advantages. W: What are they? M: Well, first of all, it has a very international vocabulary. It has many German, Dutch, French, Spanish and Italian words in it. So speakers of those languages will find many familiar words in English. In fact, English has words from many other languages as well. W: Why is that? M: Well, partly because English speakers have travelled a lot. They bring back words with them, so English really does have an international vocabulary. W: And what's the other advantage of English? M: It's that English grammar is really quite easy. For example, it doesn't have dozens of different endings for its nouns, adjectives and verbs, not like Latin, Russian, and German for example. W: Why is that? M: Well, it's quite interesting actually. It's because of the French. When the French ruled England, French was the official language and only the common people spoke English. They try to make the language as simple as possible, so they made the grammar easier. A.It is more difficult to learn than English.
B.
It is used by more people than English.
C.
It will be as commonly used as English.
D.
It will eventually become a world language.
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