图甲是温度自动报警器。控制电路中，电源电压U＝5V，热敏电阻R2的阻值与温度的关系如图乙所示：工作电路中，灯泡L标有“9V0.3A”的字样，R4为电子嗡鸣器，它的电流达到某一固定值时就会发声报警，其阻值R4＝10Ω，在R2温度为20℃的情况下，小明依次进行如下操作：闭合开关S1和S2，灯泡L恰好正常发光，此时R0的电功率为P0；将R1的滑片调到最左端时，继电器的衔铁刚好被吸下，使动触点与下方静触点接触：调节R3的滑片，当R3与R4的电压之比U3：U4＝4：1时，电子嗡鸣器恰好能发声，此时R0的电功率为P0′，P0′：P0＝4：9，已知电源电压，灯丝电阻都不变，线圈电阻忽略不计，求：
（1）灯泡L的额定功率；
（2）当衔铁刚好被吸下时，控制电路的电流；
（3）将报警温度设为50℃时，R1接入电路的阻值；
（4）工作电路的电源电压Ux。
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你校英语社团面向毕业生举行以“成为更好的自己”为主题的征文活动，请你结合自身经历，从"make friends", "have a healthy lifestyle", "develop good study habits", "take up a new hobby", "be independent” 五个方面任选一至两项，写一篇英语短文投稿。
要求:
1.词数80-100(开头已给出，不计入总词数);
2.文中不得出现真实姓名、校名等相关信息。
At the beginning of a new life, I'm going to make myself better. __________________________
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As a student, what can you do to live an environment-friendly life?文中提到的除外。
① ②
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How does the writer live a more environment-friendly life?文中任意两种即可。
① By___ _ ② By
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从文中找出与划线句子(A)意思相近的句子。
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阅读下面日记，完成小题。
Saturday 29 May
Something has changed my mind today. I saw some pictures of the sea animals influenced by the rubbish in the sea. I can't get that out of my mind. So, I am going to try and live a more environment-friendly life. (A)Each day I will keep trying to change one thing that I do to protect the earth.
Monday 31 May
Today I have decided to stop using plastic wrap (塑料保鲜膜) around the sandwiches that my mom makes for my lunch. Plastic wrap keeps my sandwich nice and fresh, and it's easy to throw away. However, I come up with a better idea. I can use a glass container (容器) instead of the plastic wrap. So, I can reuse it the next day for lunch. And I told this to my classmates too. I hope to see more reusable containers at school tomorrow.
Thursday 3 June
Good news, when I took out my glass container, I noticed more of my classmates bring their home-made lunch in their own containers to school! Tonight, when I was shopping with my mom, I found a shop which doesn't provide any plastic bags! The idea of the shop is that you bring your
own cloth bags. In this way, there are no plastic or paper bags to throw away at home. When I left the store with the buys in my own cloth bags, I felt very proud of myself. (B)Tomorrow I'm taking the bus to school to save energy.
Friday 4June
What a wonderful bus ride to school today! Well, it's been a week since I decided to try to live a more environment-friendly life. The unbelievable part is that I can actually see a difference in the garbage(垃圾) in my home. The garbage bag is lighter and only one third filled. I feel excited that I have made a real difference. I'm going to keep saving the world one day at a time.
Why did the writer decide to live a more environment-friendly life?
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