Need some help with UNIXLinux scripting particularly the sed

Need some help with UNIX/Linux scripting, particularly the sed command:

Consider the address book below:

$ cat addr

Xiao Li, lxiao@unc.edu, 6705462234, Jackson, NC 764
Natkin William, wnatkin@imap28.vcu.edu, 8044344528, Richmond, VA 22345 Elizi Moe, emoe@ncsu.edu, 5208534566, Tempe, AZ 85282
Ma Ta, mta@yahoo.com, 4345667345, Austin, TX 91030
Diana Cheng, dcheng@asu.edu, 5203456789, Matitsi, WY 4587
Jackson Five, jfive@ncsu.edu, 5206564573, Kyenta, AZ 85483
Adi SrikanthReddy, sadi1@imap1.asu.edu, 6578904566, Wyo, WS 67854

Sort the addr file by phone number and print lines 1 thru 3. (Please use the sed command)

Solution

#!/bin/bash

sort -k 3 addr.txt > addr1.txt
# we used -k to add more fileds to sort. here we will sort based upon 3rd row and result will store in addr1.txt
sed -n \'1p\'|awk \'{print $1,$2,$3}\'