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问题 单项选择题

统计学上说的系统误差、测量误差和抽样误差3种误差，在实际工作中（）

A.3种误差都不可避免

B.系统误差和抽样误差不可避免

C.系统误差和测量误差不可避免

D.测量误差和抽样误差不可避免

E.3种误差都可避免

答案

参考答案：D

填空题

People use money   86  food, books, bicycles and hundreds of other things they   87  .When they   88  ,they usually get paid in money.

Most of the money used today   89  metal or paper. But in ancient times people often used all kinds of things as money. One of the first kinds of money was shells（贝壳）.

In ancient China, cloth and knives   90  money. Elephant tusks（象牙）,monkey tails（尾巴）and salt were used in some parts of Africa. Rice was also a kind of money used by the ancient people on some islands. Cows and other animals were used as money. too.

The first copper（铜）coins   91  China. They were round and had a square（正方的）hole in the center. Different countries have used different metals for their money. Later some countries   92  to make coins of gold and silver（银）.But gold, silver and copper were heavy   93  when people needed a lot of coins to buy something expensive. The Chinese were the first   94  paper money. The first paper money didn’t   95  like the paper money we use today.
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单项选择题

就知识产权中的财产权而言，其基本特征之一是具有法定保护期的限制，但是并非知识产权中每一项财产权都具有时间限制。根据知识产权法的有关规定，正确的说法是 ______。

A．厂商名称权、商业秘密权、商标权均有法定保护期限

B．厂商名称权、商标权有法定保护期限，商业秘密权无法定保护期限

C．厂商名称权、商业秘密权和商标权均无法定保护期限

D．厂商名称权、商业秘密权无法定保护期限，商标权有法定保护期限
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