单项选择题 HowdoestheweightypropertyoftheGridBagConstraintsobjectsusedingridbaglayoutaffectthelayoutofthecomponents？（）

多项选择题 Which lines of code are valid declarations of a native method when occurring within the declaration of the following class？（）    public class Qf575 {   // insert declaration of a native method here   }

单项选择题 What will be written to the standard output when the following program is run？（）   class Base {  int i；  Base（） {   add（1）；   }   void add（int v） {  i += v；  }   void print（） {  System.out.println（i）；  }   }   class Extension extends Base {  Extension（） {  add（2）；  }   void add（int v） {  i += v*2；  }  }   public class Qd073 {   public static void main（String args[]） {  bogo（new Extension（））；  }   static void bogo（Base b） {  b.add（8）；  b.print（）；   }   }