为了提高LF炉的加热效率，精炼时要求实现（）加热。 A.裸弧 B.埋弧 C.半裸半埋

某一实验室血糖参加室间质量评价活动，五个标本中有两个结果不在可接受范围之内，得分为60%，并且其偏倚均为正的偏倚，可提示测定系统存在误差类型()

A．随机误差

B．过失误差

C．操作误差

D．系统误差

E．试剂误差

在票据与粘单连接处应入如何签章？签章时应注意哪些事项？

The White Tower

The White Tower was started in 1076 and completed in 1079. It was the oldest of the 20 towers which used to stand here. The white tower of London was first built by William, the conqueror to protect and control the city. Today it is the most popular tourists sight and attracts over three million visitors a year.

It was sometimes used as a palace for the kings and queens of English until the time of James I, but it is best known as a prison and execution place. Within the walls of the Tower, princes have been murdered, spies shot and Queens killed. One of the most famous executions was that of Ann Boleyn in 1536. She was killed because she couldn’t give Henry III a son.

The tower was also the scene of one of London’s most famous mysteries, known as the mystery of the princes in the Tower. Their uncle announced he himself was the new king and asked the people to call him Richard III. After that the two boys disappeared. It was the two sons that were murdered by the order of their uncle.

68. The Tower of London ________.

A. was started in the tenth century and finished in the eleventh century

B. is the oldest tower in the world

C. was first put up by James I

D. was built to protect and control London

69. The tower was used as a palace_______.

A. till the time James I

B. until the time of William, the conqueror

C. after James I came to power

D. when James I came to power

70. Anne Boleyn was put to death because she______.

A. didn’t get on well with Henry III

B. couldn’t give birth

C. couldn’t give Henry III a son

D. turned against her husband

71.They say who killed two sons of Edward IV?

A. Edward IV    B. Richard III      C. Anne Boleyn      D. James I

公司还将结合境外单位HSE总监（）工作，跟踪“4+4工作法”的实施。

A.管理

B.述职

C.培训

D.现场

试述保护接地和保护接零的适用范围？