问题 多项选择题

起重机操作中电气对人身的伤害主要是()所产生的电弧烧伤。

A、触电

B、短路

C、电击

D、电伤

答案

参考答案:A,B

问答题
材料题

阅读下列材料:

        材料一:乾隆帝致英国国王乔治三世的信中说:“天朝物产丰盈,无所不有,原不藉外夷货物以通有无。”

       材料二:清嘉庆帝上谕说:“天朝富有四海,岂需尔小国些微货物哉?”

(1)这些材料说明我国当时实行的是一种什么政策?为什么实行这种政策?

                                                                                                                                                             

                                                                                                                                                             

                                                                                                                                                             

(2)这种政策的含义是什么?

                                                                                                                                                             

(3)联系当前现实谈谈你从中得到什么启示?

                                                                                                                                                             

(4)你认为在对待外来事物方面今天我们应如何去做?