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Use of the [Krull topology](Krull%20topology)
![](attachments/Pasted%20image%2020220126231943.png)
![](attachments/Pasted%20image%2020220126232012.png)
![](attachments/Pasted%20image%2020220126232036.png)
![](attachments/Pasted%20image%2020220126232100.png)
![](attachments/Pasted%20image%2020220126232146.png)