Can someone please help me with this Linux/Unix question? I've had to ask this question twice now

 Write a script named long_file.sh to find the longest file name in a directory. long_file.sh will accept a directory name as the first argument and determine the longest filename in that directory. If the correct number of arguments are not provided, print an error message to standard output and exit the script with a return error of 1. If the scripts's first argument is not a directory name, print an error message to standard output and exit with a return code of 1. If a the first argument is a directory, print the directory name prior to printing the longest filename and length. If there are multiple files with the same length, you may print the first one found. You may print multiple filenames for 5 bonus points. (See GRADUATE student requirements below). Example run: $ ./long_file.sh /home/michelle/temp Directory: /home/michelle/temp Longest filename: longerfilenameishere Longest filename len: 20 Directory listing from test directory $ ls /home/michelle/temp file1 file2 file3 file4 longerfilenameishere Example run 2: $ ./long_file.sh Usage: ./long_file.sh directory Example run 3: $ ./long_file.sh file1 First parameter must be a directory (file) Rubric: 50 points Correct script name: 5 Check for valid parameters: 5 points Check for directory: 5 points Print out correct filename: 5 points Print out correct length: 10 points (Documentation) Reasonable comments in code 10 (Coding standards) Accepted programming standarrd and conventions 10