Although zip files can be used in a Linux environment with commands like zip and unzip, avid Linux users typically prefer to use tar files instead. A tar file (sometimes called a tarball) is a file that combines the content and metadata of multiple files into a single file, often with compression using algorithms like gzip or bzip2.

Suppose you have a tar file named data.tar.gz. You want to identify how many files with the extension .xlsx this file includes. Check the man pages for the tar command and other relevant commands to obtain this information. Your output should include a single number, the count of the number of files with that extension, and nothing more. No files should be extracted, i.e., you should use the tar command only to list the files in the tar file, not to create or extract another file. Here are a few other commands that may be useful:

• The tar command itself already provides the means to find files based on a wildcard pattern. Using commands like grep to filter the output based on a string is also a valid alternative. If you use that option, though, make sure you only consider the end of the file name as the extension, and do not include files like file.xlsx.dat.
• The wc command can provide information about the number of lines, characters or words in an input.