7. A two dimensional code with m rows and n columns has two parity rows and one parity column. One of the parity rows is the even parity over the column information bits. The other parity row and the parity column are the parities over the cross-data bits (see the figure below). Show that the code can correct any number of errors in a row. Explain the error correcting scheme. (A variation of this code is used in IBM magnetic tapes and disks) parity bit over the diagonal cross parity parity over column