CECS 424 Assignment 6 Count the word frequencies in as6.txt. Erlang uses a list of tuples as a hash table. Write four Erlang functions. 1. This function has a string file name parameter and returns a list of words in the file. Open the file with file:open. The file as6.txt was written in Notepad as one line so io:get_line will read the whole file. string:tokens will separate it into words. Its second argument specifies all the delimiters. 2. This function has two parameters, a string word and a list of tuples, and returns a list of tuples with the word added appropriately. Each tuple is a word key and a frequency value. The lists:keyfind method will find a tuple if it exists and return false if it does not. If the word is not found use lists:append to add a tuple with the word as key and 1 as the frequency. If the word is found use lists:keyreplace to replace the tuple with a new tuple with frequency increased by one.3. This function has a list of words as parameter and returns a hash table of tuples of words and their frequencies. The string:to_lower method will make a word lower case to provided the desired case insensitivity.  Use the lists:foldl method to build the answer using the function 2.4. This function outputs the final hash table sorted by frequency from high to low using the lists:sort function. Its one parameter is the file name. It uses functions 3 and 1.