著名的历史学家希罗多德说，E国是“尼罗河的馈赠”，其中的“E国”是指（） A．古

根据短文内容，判断正(T)误(F)。

     There are eighteen boys and twenty-five girls in our class. One of the boys is English. His name is

Tom. He is thirteen. Two of the girls are American. They are twins. Their names are Jane and Joan.

They are twelve. They are my friends. All of the Chinese boys and girls are Young Pioneers (少先队

员). We all Chinese students like (喜欢) the English boy and the American girls, and they like us, too.

We help each other.

( )1. In our class there are forty-three students.

( )2. The twin sisters are from England.

( )3. Joan is twelve, and Tom is thirteen.

( )4. All the students in our class are Young Pioneers.

( )5. We like American and English students.

某工厂的机电安装工程由某机电公司负责。由于工程施工时间有限，施工单位为尽快完成任务，决定在每晚加班2h赶工。因施工现场用电设施不全面，影响施工质量，于是施工单位向供电部门申请临时用电，并根据国家有关标准、规范和施工现场的实际负荷情况，编制施工现场《临时用电施工组织设计》，并向当地电业部门申报用电方案。施工单位依照《中华人民共和国电力法》安装用电计量装置，按照《施工现场临时用电安全技术规范》用电，并进行检查验收，既保证了用电安全，也保证了施工质量，取得很好的效果。

国家对电力建设、生产、供应和使用活动的管理原则是实行( )。

A．安全用电

B．节约用电

C．计划用电

D．计量用电

E．文明用电

填写实验报告

涂刮腻子时应注意些什么？

观察单位数不确定的总体称为有限总体。