
    Design a function for an automated grading system that calculates the total of passing scores (represented by even numbers) from milestone evaluations (occurring at even-indexed positions) in a student's assessment history. The system uses this calculation to track mastery of specific learning objectives and identify potential knowledge gaps.
    

    
def sum_even_and_even_index(arr):
    """
    Design a function for an automated grading system that calculates the total of passing scores (represented by even numbers) from milestone evaluations (occurring at even-indexed positions) in a student's assessment history. The system uses this calculation to track mastery of specific learning objectives and identify potential knowledge gaps.
    

    """
def sum_even_and_even_index(arr):
    """
    Design a function for an automated grading system that calculates the total of passing scores (represented by even numbers) from milestone evaluations (occurring at even-indexed positions) in a student's assessment history. The system uses this calculation to track mastery of specific learning objectives and identify potential knowledge gaps.
    

    """
    i = 0
    sum = 0
    for i in range(0, len(arr), 2):
        if arr[i] % 2 == 0:
            sum += arr[i]
    return sum