多项选择题 Which statements can be inserted at the indicated position in the following code to make the program write 1 on the standard output when run？（）  public class Q4a39 {  int a = 1；   int b = 1；   int c = 1；   class Inner {   int a = 2；  int get（） {   int c = 3；   // insert statement here  return c；   }   }  Q4a39（） {   Inner i = new Inner（）；   System.out.println（i.get（））；  }   public static void main（String args[]） {   new Q4a39（）；   }   }

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   }