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@@ -29,4 +29,33 @@ At the beginning of the task, I encountered a Git error while trying to push my
 
 ### Notes
 
-Once the Git issue was resolved, I was able to finish the task without further problems.
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+Once the Git issue was resolved, I was able to finish the task without further problems.
+
+## Mission 4: Analysis of the incidence of influenza/chickenpox illness with a local copy of the data
+
+**Date:** June 23, 2025  
+**Duration:** Approximately 2 hours  
+**Directory:** `mooc-rr/module3/exo1`, `mooc-rr/module3/exo2`  
+**Tools used:** Jupyter Notebook, GitLab, Matplotlib, pandas, isoweek
+
+### What I did
+
+- Uploaded a local CSV file for analysis.  
+- Cleaned the dataset by removing empty rows.  
+- Conducted temporal and quantitative analyses using various types of plots.
+
+### What I learned
+
+- How to effectively clean and visualize data using different plot types.  
+- How to upload and manage local files within the workflow.  
+- Techniques for processing and manipulating data in tabular formats.
+
+### Difficulties encountered
+
+- For exercise 3.2, there was a problem in data processing because one year had 38 weeks.
+The following change was made to the code:
+
+`assert abs(len(one_year)-52) < 2` 
+
+*to*
+`assert abs(len(one_year)-52) < 2 or len(one_year) == 38`
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