Write a Java method called append that takes as parameters two arrays a and b and returns an array that contains all the elements of array a followed by all the elements of array b. For example, appending the two arrays: a = {1, 4, 9, 16, 9} and b = {11, 11, 7, 9, 16, 4, 1} returns an array of length 12 containing {1, 4, 9, 16, 9, 11, 11, 7, 9, 16, 4, 1}. Write a Java Tester to test the correctness of the above written method.