Which of the following commands can be used to extract content from a tar file?

What is the output of the following command?
for token in a b c; do
echo -n ${token};
done

Which character starts a comment line in a shell script file?

What does the exit status 0 indicate about a process?

Given a file called birthdays containing lines like:
YYYY-MM-DD Name
1983-06-02 Tim
1995-12-17 Sue
Which command would you use to output the lines belonging to all people listed whose birthday is in May or June?

Which of the following programs is used to search for files in a file system?

While deleting all files beginning with the letter a there was still the file Access.txt left. Assuming that it had the correct ownership, why was it not deleted?

When creating a new file, what can be done to make the file hidden from the default output of the ls command?

Which command line can be used to search help files that mention the word “copy”?

Which command shows if /usr/bin is in the current shell search path?