Write a class named MatrixSum with the following two methods and functionality:

1. Write a main method to prompt the user to enter a 3 by 4 matrix row by row.

Have this method to reads and builds a multidimensional array which houses the 3 by 4 matrix

Have this method to call the sumColumn method to produce the column sum.

Have this method to display the sum of each column

2. Write a sumColumn method that returns the sum of all the elements in a specified column in a matrix using the following header:

public static double sumColumn( double[][] m, int columnIndex )

Heres a sample run:

Enter a 3 by 4 matrix row by row:

1.4 2 3 4 [ENTER]

5.5 6 7 8 [ENTER]

9.5 1 3 1 [ENTER]

Sum of the elements at column 0 is 16.4

Sum of the elements at column 1 is 9.0

Sum of the elements at column 2 is 13.0

Sum of the elements at column 3 is 13.0