Update 2 files

- /0013_how_to_benchmark.md
- /files/0013_cover_02.png

Author: NikolayS

0013_how_to_benchmark.md

@@ -4,7 +4,7 @@ Originally from: [tweet](https://twitter.com/samokhvalov/status/1711237471743480
 
 # How to benchmark
 
-<img src="files/0013_cover.png" width="600" />
+<img src="files/0013_cover_02.png" width="600" />
 
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