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【简答题】
回答下列问题: (1)杂交育种是通过品种间杂交创造新类型的育种方法。其特点是将两个纯合亲本的________通过杂交重组在一起，再经过选择和培育获得新品种。 (2)若两个纯合亲本杂交，F 1 自交能产生多种非亲本类型，其主要原因是F 1 在形成配子时，位于________基因自由组合，或者位于________基因通过非姐妹染色单体交换进行重新组合。 (3)假设杂交涉及到n对相对性状，每对相对性状各受一对等位基因控制，彼此间各自独立遗传。在完全显性的情况下。从理论上讲，F 2 中表现型共有________种，杂合子基因型共有________种。 (4)从F 2 ，一般还要进行多代自交和选择。自交的目的是________；选择的目的是________。
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【简答题】区分岩石坚固程度所用的系数叫普氏系数，其符号为“f”，计算公式为（），其中R为岩石极限单向抗压强度（Mpa）。
【单选题】- How many people attended the exhibit? - I’m not sure. __________ 100 people.
A.
Exactly
B.
Actually
C.
Roughly
D.
Strictly
【单选题】She is a very talented ___________, and many people admire the glass vases and bowls she creates.
A.
carpenter
B.
craftsperson
【单选题】People may have different opinions about Karen, but I admire her. ______, she is a great musician.
A.
After all
B.
As a result
C.
In other words
D.
As usual
【单选题】已知某隧洞开挖断面为城门洞形，开挖宽度B及高度H均为5.5m，围岩为比较新鲜的、节理裂隙较少的砂岩，岩石坚固系数f=6，摩擦角为75°，容重为24kN/m 3 ，采用普氏公式计算该断面的垂直山岩压力为( )kN/m 2 。
A.
9.73
B.
8.73
C.
7.62
D.
6.31
【单选题】One of the qualities that most people admire in others is the willingness to admit one's mistakes. It is extremely hard sometimes to say a simple thing like 'I was wrong about that,' and it is even ha...
A.
have never made any mistakes
B.
often make mistakes but correct them in no time
C.
admit their mistakes
D.
forget other people's mistakes easily
【单选题】One of the qualities that most people admire in others is the willingness to admit one's mistakes. (79) It is extremely hard some times to say a simple thing like 'I was wrong about that,' and it is e...
A.
About 8.
B.
About 18.
C.
About 23.
D.
About 15.
【简答题】阅读理解。 One of the qualities that most people admire in others is the willingness to admit one's mistakes. It is extremely hard sometimes to say a thing like 'I was wrong about that,' and it is e...
【简答题】下面是某公司2005年1～5月份销售电脑台数情况统计表。 某公司销售电脑台数情况统计表 （1）（ ）月份的销售量最高。 （2）（ ）月份的销售量最低，销售了（ ）台电脑。 （3）销售量排在第二位的是（ ）月。 （4）（ ）月销售了3400台电脑。 （5）1月比3月少销售（ ）台电脑。 （6）这5个月来总的销售量呈（ ）趋势。
【简答题】He is one of the greatest __________ (physics) in the world and many people admire him very much.
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