A. private String num=null; B. public String num=null; C. private int num=null; D. public int num=null;
A. private String username=null; B. public String username=null; C. private int username=null; D. public int username=null;
A. private int num=null; B. public int num=null; C. private double num=null; D. public double num=null;
A. page B. request C. response D. session
A. page B. request C. session D. application
A. name B. property C. scope D. param