Write the results of each of the following Linux commands using regular expressions for the above-mentioned file.
# x1. <span style="font-family:courier;font-weight:bold">grep "^[-+]" ~murray.saul/uli101/numbers.txt</span> 2. <span style="font-family:courier;font-weight:bold">grep "^[-+]*.[0-9]" ~murray.saul/uli101/numbers.txt</span> 3. <span style="font-family:courier;font-weight:bold">grep "^[+-]?[0-9]" ~murray.saul/uli101/numbers.txt</span><br>(Why?) 4. <span style="font-family:courier;font-weight:bold">egrep "^[+-]?[0-9]" ~murray.saul/uli101/numbers.txt</span> 5. <span style="font-family:courier;font-weight:bold">egrep "^[+-]?[0-9]+$" ~murray.saul/uli101/numbers.txt</span> 6. <span style="font-family:courier;font-weight:bold">6. egrep "^[+-]?[0-9]+[.]?[0-9]+$" ~murray.saul/uli101/numbers.txt</span>