Problem 1

 public class Main {

  int x = 10;

  double PI = 3.14;

  public static void main(String[] args) {

    Main myObj = new Main();

    myObj.x = 50; // will generate an error

    myObj.PI = 25; // will generate an error

    System.out.println(myObj.x); 

  }

}

// output 50