（）指的是英国中世纪以来的法和以此为传统或受其影响而发展起来的其他国家的法的总称。

13， 10， 4， 7，-2，( )

A．-9

B．-12

C．10

D．11

A majority of HDTV consumers could not enjoy high-quality digital pictures because ______.

A．they did not tune in to the right channel

B．they did not install the system

C．the market retailers created the confusion on purpose

D．the manufacturers did not have a uniform standard for their sets

根据表“股票”和“数量”建立一个查询，该查询包含的字段有“股票代码”、“股票简称”、“买入价”、“现价”，“持有数量”和“总金额”(现价*持有数量)，要求按“总金额”降序排序，并将查询保存为myquery。 (2)打开myprog程序，该程序包含3条SQL语句，每条语句都有一个错误。请更正之。

As agreed upon in our negotiations, payment ( )L/C.

A．by

B．will be

C．is to be made by

D．is by

工作线对之间及全部芯线与铅皮之间应能承受交流50赫500伏的电压（）分钟不击穿。

A、3

B、5

C、2