Write a bash shell script to carry out each of the following tasks:

a. Backup:

Archive as a "tarball" (*.tar.gz file) all the files in your home directory tree (/home/your-name) that have been modified in the last 48 hours. Hint: use the command find.

b. Phone:

Write a shell script (called phone) that creates a simple telephone list (create an empty file called phonelist in your home directory). Each line in this file consists of two fields: a name and a phone number. The script shall do the following:

1. When the user types the command: phone new name number this will add new record (name, number) to the list.

2. When the user types the command: phone name then the script should search in the file phonelist and get the corresponding phone number and display the result.