Can anyone help me with this JAVA question. I am really stuck! Thank you

Write a Java program to calculate the mean intensity value of image int img[][]. The size of the image is numRows by numColumns, and the intensity value at (i,j) is img[i][j]. Please fill in the following code in // TODO.

public class MeanIntensity {

public int calcMeanIntensity(int img[][],int numRows, int numColumns) {

// TODO: please write your code here

}

}