Update bash-extracting_from_files.md

docs/pages/bash/bash-extracting_from_files.md

@@ -115,10 +115,12 @@ Sort is particularly useful when you use some key options:
 !!! question "Look at the first lines after sorting numerically. Do you observe any difference?"
 
 
-```bash
-sort nat2021.csv | head
-sort -n nat2021.csv | head
-```
+??? example "Click to show the solution"  
+
+    ```bash
+    sort nat2021.csv | head
+    sort -n nat2021.csv | head
+    ```
 
 
 !!! question "Which name was the most popular among all records? Which year?"
@@ -146,12 +148,12 @@ The `cut` command allows to cut a line at a specific character and extract a sel
  * `-d` specify the separator  
  * `-f` specify the field to extract   
 
-!!! question "How to extract the name of the top 100 names/year the most provided"
+!!! question "Combining with `sort` command, how can you extract the name of the top 30 most popular names and the corresponding year"
 
 ??? example "Click to show the solution"  
     ```bash
     # command
-    sort -n -t ';' -k4  nat2021.csv | tail -n 100 | cut -d";" -f 2
+    sort -n -t ';' -k4  nat2021.csv | tail -n 30 | cut -d";" -f 2,3
     ```
 
 The `uniq` command can be used to remove the redundancy. But result need to be sorted to make it work properly/