In C:

7. Let us define the weighted sum of an integer array a[0], a[1], a[2], , a[n-1] be a[0]*1 + a[1]*2 + a[2]*3 + +a[n-1]*n. For example, the weighted sum of the array [5,2,6] would be 5*1+2*2+6*3 = 27. Write a recursive function that takes in an array numbers and its length n, and returns its weighter sum. You can assume n is non-negative integer.

int weightedSum(int numbers[], int n) {