For this assignment, you will complete two separate classes which will be used to find statistics from arrays. The first class, NumStatsArray, needs to store an array of doubles as a member variable. This should be declared as private and final, so none of your methods will set this variable to point at a different array. The single constructor for this class has a parameter of a double array, and should set the member variable to point to this parameter array. You will need to complete the following methods in the NumStatsArray class (you may assume that the member variable array is not empty when writing these methods):
toString - returns a String with the array contents in the form {1.0, 4.0, 5.0}. Note that there is a comma then a single space between each pair of elements, but there are no spaces/commas at the start/end, only curly braces.
average - returns the arithmetic mean average of the numbers in the array as a double. This is found by dividing the sum of the numbers by the amount of numbers in the array (note: some values returned may be slightly inaccurate due to roundoff errors, which you do not need to worry about for this assignment).
range - returns a double found by subtracting the smallest number in the array from the largest number in the array
sortStatus - returns an int which is equal to 1 if the array is sorted in increasing order, -1 if it is sorted in decreasing order or 0 if it is not sorted. The array is sorted in increasing order if every number is greater than or equal to the previous number. The array is sorted in decreasing order if every element is less than or equal to the previous number. If neither of these is true then the list is unsorted. If every element in the array is the same, then it is counted as being in increasing order.

Write a program to analyze student’s scores. each student’s id and 4 original test scores are saved in the attached file “student_id_scores.txt”. assume there are exactly 15 students in the class.• the program first opens the file, reads student’s ids and scores from the file and saves them in two arrays: o create a one-dimensional string array “ids” to store the student’s ids.o create a (parallel) two-dimensional int array “scores” to store student’s original test scores. this array has 5 columns, the original 4 test scores should be saved in the first 4 columns, and the last column will be used to save the average score after the calculation in next step.• the program then retrieves test scores from the array “scores”, calculates average score and determines the final letter grade based on the rules in the table below for each student. assume average score is integer value.average score = (score1 + score2 + score3 + score4) / 4average score letter grade90 ~ 100 a80 ~ 89 b70 ~ 79 c60 ~ 70 d0 ~ 60 f• the average score should be saved back in the 5th column of “scores” array.• create a new parallel one-dimensional char array “grades” to save each student’s letter grade.• program also needs to find the number of a, number of b, number of c, number of d and number of f grade. as well as the highest, lowest and average score of the class.• finally, program will display all of the original scores and all results on the computer screen using the format shown as the sample output below.• the program must contain at least the following functions: (1) a function “getscores” to read and store data into “ids” and “scores” arrays.(2) a function “analyzescores” to calculate student’s average score, determine letter grade, get the number of a, b, c, d and f, find the highest, lowest and average score of the class.(3) a function “displayresults” to display all of the results