minor fixes on wc -l numbers

Author: DininduSenanayake

docs/04-redirection.md

@@ -274,7 +274,7 @@ of your kid's first birthday party, you also want to avoid overwriting your data
     ```
 
     ```output
-    802 bad_reads.txt
+    537 bad_reads.txt
     ```
 !!! terminal "code"
 
@@ -300,7 +300,7 @@ search sequence. So our file was overwritten and is now empty.
     ```
 
     ```output
-    802 bad_reads.txt
+    537 bad_reads.txt
     ```
 
     ```bash
@@ -309,7 +309,7 @@ search sequence. So our file was overwritten and is now empty.
     ```
 
     ```output
-    802 bad_reads.txt
+    537 bad_reads.txt
     ```
 
 The output of our second call to `wc` shows that we have not overwritten our original data.
@@ -322,7 +322,7 @@ The output of our second call to `wc` shows that we have not overwritten our ori
     ```
 
     ```output
-    802 bad_reads.txt
+    537 bad_reads.txt
     ```
 
 
@@ -412,15 +412,15 @@ number of lines. Luckily, this issue happens by the end of the file so we can al
     #!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
     ```
 
-The fifth and six lines in the output display "--" which is the default action for `grep` to separate groups of
+The sixth line in the output display "--" which is the default action for `grep` to separate groups of
 lines matching the pattern, and indicate groups of lines which did not match the pattern so are not displayed.
 To fix this issue, we can redirect the output of grep to a second instance of `grep` as follows.
 
 !!! terminal "code"
 
     ```bash
-    $ grep -B1 -A2 NNNNNNNNNN SRR098026.fastq | grep -v '^--' > bad_reads.fastq
-    $ tail bad_reads.fastq
+    $ grep -B1 -A2 NNNNNNNNNN SRR098026.fastq | grep -v '^--' > bad_reads.txt
+    $ tail bad_reads.txt
     ```
 
     ```output
@@ -436,10 +436,10 @@ To fix this issue, we can redirect the output of grep to a second instance of `g
     #!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
     ```
 
-The `-v` option in the second `grep` search stands for `--invert-match` meaning `grep` will now only display the
-lines which do not match the searched pattern, in this case `'^--'`. The caret (`^`) is an **anchoring**
-character matching the beginning of the line, and the pattern has to be enclose by single quotes so `grep` does
-not interpret the pattern as an extended option (starting with --).
+    The `-v` option in the second `grep` search stands for `--invert-match` meaning `grep` will now only display the
+    lines which do not match the searched pattern, in this case `'^--'`. The caret (`^`) is an **anchoring**
+    character matching the beginning of the line, and the pattern has to be enclose by single quotes so `grep` does
+    not interpret the pattern as an extended option (starting with --).