19. Given the following script, alter it so that all output is sent to the file script_output.txt. #1/bin/bash echo Hello SUSERNAME echo Today's date is 'date echo Your current directory is $PWD 20. What is wrong with the following script? #1/bin/bash FIRST-Frank SECOND-Zappa FULL-?FIRST $SECOND echo $FULL a. There should be quote marks around $FIRST $SECOND b. There should be no $ before FIRST, SECOND or FULL c. There should be quote marks around Frank and around Zappa d. You did not declare the variables FIRST, SECOND and FULL e. There is nothing wrong with the script