阅读材料，回答问题：

材料一：我们是东海捧出的珍珠一串，琉球是我的群弟我就是台湾。我胸中还氤氲着郑氏的英魂，精忠的赤血点染了我的家传。母亲，酷炎的夏日要晒死我了；赐我个号令，我还能背城一战。母亲！我要回来，母亲！

──闻一多《七子之歌·台湾》（1925年）

材料二：三国之宗旨，在剥夺日本自1941年第一次世界大战开始以后在太平洋上所夺得或占领之一切岛屿，在使日本所窃取于中国之领土，例如满洲、台湾、澎湖列岛等，归还“中华民国”。

──中美英《开罗宣言》（1943年）

（1）材料一中“郑氏的英魂”指的是哪一历史事件？指出材料一中“酷炎的夏日要晒死我了”的含义。

（2）材料二的规定对台湾问题有什么历史意义和现实意义？​

若复数z满足$z·i=1+i$，那么$z=( \; )$

Here are some tips on listening. We hope it can help you in one way or another.
●Relax yourself.
Before you start to listen to something, You need to relax.
____  This will help you with your listening.
●Listen carefully to the first sentence.
____  For example, if eyou hear“Many shops in many parts of China have decided to take away all kinds of Japanese goods off their shelves, but some people say it's not a good idea. Our reporter says…”,you know you will hear a piece of news, not a children's story or a science report.
●Think when you're listening.
____ For example, you can think of the following questions: What happened? When , where and how? What was the result and what does the speaker want to tell us? In this way, you may undersrand the passage better.
●Listen for important facts.
____  For example, if the passage is a science report, you should try to remember its findings , and how the scientists got their results. 
●Don't think about one or two words for too long.
You may hear some words that you don't know. But don't spend too much time on them.
____  But you can remember some words or sentences that you think are important, and you can use them when you’re answering the questions.

 如图是某电饭锅的简化电路图。S₁、S₂都闭合时是加热状态，总功率为是800W；只闭合S₂时是保温状态，R₂的电阻是1100Ω。家庭电路的电压是220V。试求：

(1)保温状态时，R₂的功率是多少?
(2)加热状态时，总电流是多少?R₁的电阻是多少?(计算结果保留小数点后两位)
(3)加热状态时，电饭锅工作30 min，产生的热量是多少