Answer: Provided in the explanation segment
Explanation:
Below is the code to carry out this program;
/* C++ program helps prompts user to enter the size of the array. To display the array elements, sorts the data from highest to lowest, print the lowest, highest and average value. */
//main.cpp
//include header files
#include<iostream>
#include<iomanip>
using namespace std;
//function prototypes
void displayArray(int arr[], int size);
void selectionSort(int arr[], int size);
int findMax(int arr[], int size);
int findMin(int arr[], int size);
double findAvg(int arr[], int size) ;
//main function
int main()
{
   const int max=50;
   int size;
   int data[max];
   cout<<"Enter # of scores :";
   //Read size
   cin>>size;
   /*Read user data values from user*/
   for(int index=0;index<size;index++)
   {
       cout<<"Score ["<<(index+1)<<"]: ";
       cin>>data[index];
   }
   cout<<"(1) original order"<<endl;
   displayArray(data,size);
   cout<<"(2) sorted from high to low"<<endl;
   selectionSort(data,size);
   displayArray(data,size);
   cout<<"(3) Highest score : ";
   cout<<findMax(data,size)<<endl;
   cout<<"(4) Lowest score : ";
   cout<<findMin(data,size)<<endl;
   cout<<"(5) Lowest scoreAverage score : ";
   cout<<findAvg(data,size)<<endl;
   //pause program on console output
   system("pause");
   return 0;
}
  
/*Function findAvg that takes array and size and returns the average of the array.*/
double findAvg(int arr[], int size)
{
   double total=0;
   for(int index=0;index<size;index++)
   {
       total=total+arr[index];
   }
   return total/size;
}
/*Function that sorts the array from high to low order*/
void selectionSort(int arr[], int size)
{
   int n = size;
   for (int i = 0; i < n-1; i++)
   {
       int minIndex = i;
       for (int j = i+1; j < n; j++)
           if (arr[j] > arr[minIndex])
               minIndex = j;
       int temp = arr[minIndex];
       arr[minIndex] = arr[i];
       arr[i] = temp;
   }
}
/*Function that display the array values */
void displayArray(int arr[], int size)
{
   for(int index=0;index<size;index++)
   {
       cout<<setw(4)<<arr[index];
   }
   cout<<endl;
}
/*Function that finds the maximum array elements */
int findMax(int arr[], int size)
{
   int max=arr[0];
   for(int index=1;index<size;index++)
       if(arr[index]>max)
           max=arr[index];
   return max;
}
/*Function that finds the minimum array elements */
int findMin(int arr[], int size)
{
   int min=arr[0];
   for(int index=1;index<size;index++)
       if(arr[index]<min)
           min=arr[index];
   return min;
}
cheers i hope this help!!!