In the provided code, x is an instance variable and y is a static variable. The values of x are unique to each instance of the Tester class, while y is shared among all instances. When t1.x is set to 2 and Tester.y is set to 3, it modifies the class variable y. When t2.x is set to 4 and t2.y (which is Tester.y) is set to 5, it changes the class variable y to 5 for all instances. Therefore, the output would be: 2,5 (t1.x = 2 and Tester.y = 5), 4,5 (t2.x = 4 and Tester.y = 5), 4,5 (t2.x = 4 and Tester.y = 5).