Write a class lab7b that implements the following methods: public static int[] getrow(int[][] a, int i) { // returns row number i out of the specified array a[][] // fixme // check that i is within range of valid indexes for a, else return null // return row (this is a one-dimensional array) } public static int[][] copy(int[][] a) { // returns a copy of the specified array a[][] // assume each row in `a` has the same number of columns // fixme : make a new 2-d array the same dimensions as a // row size is a. length. column size is a[0].length // fill the new array with contents of a // return the new array } public static boolean equals(int[][] a, int[][] b) { // returns false unless the two arrays have the same dimensions // and the same elements at each position // fixme: // if a does not have same number of rows as b, return false // in a nested loop, check that a and b have same number of columns, else return false // check that each a[i][j] is same as b[i][j], else return false // return true if all is well }