Create variables and assigning a value to it: a$.$ Type DOG$=$Shepherd and press enter b$.$ Type echo DOG and press enter. What do you see? c$.$ Type echo $DOG. What do you see? d$.$ Create variable call it MEMO and assign the value $$Meeting will be today at noon$.$ f$.$ e$.$ Show the variable name Print the content of it$.$ Practice arithmetic operations a$.$ Type let X$=10+2*7$ b$.$ Print the content of X c$.$ Assign $($X$+2*4)$ to the variable Y d$.$ Print the content of Y The export command a$.$ Create a script called testscript b$.$ Its content will be : echo $MY$\_$VAR c$.$ Make the script executable d$.$ Assign the value $2$ to MY$\_$VAR e$.$ Execute the script. What do you see? f$.$ Type export MY$\_$VAR g$.$ Execute the script again. What do you see now? Use the grep command to find the username $$rtml$0007$ in $/$etc$/$passwd: grep $-$i $"$rtml$0007"/$etc$/$passwd Write a shell script that prompts the username to be entered as a command line argument and call it user: grep $-$i $"$$$1"/$etc$/$passwd Exercise $7$ Introduction to shell scripting $6.7.$ Run the script as follows: a$.$ user rtml$0007$ b$.$ user fielder Change your program to prompt the user for a name to search for in the telephone book. Your program should now look something like the following: echo "Enter a name to search for: $"$ read name grep $-$i $name $/$etc$/$passwd now run the script and enter your user name to be searched for.