1Which of the following fragments might cause errors (5%)
　　A. String s = “Gone with the wind”;
　　String t = ” good “;
　　String k = s + t;

　　B. String s = “Gone with the wind”;
　　String t;
　　t = s[3] + “one”;

C. String s = “Gone with the wind”;
　　String standard = s.toUpperCase();

　　D. String s = “home directory”;
　　String t = s – “directory”;

2 public class Parent { (5%)
　　public int addValue( int a, int b) {
　　int s;
　　s = a+b;
　　return s;
　　}
　　}
　　class Child extends Parent {

　　}
　　Which methods can be added into class Child
　　A. int addValue( int a, int b ){// do something…}
　　B. public void addValue (){// do something…}
　　C. public int addValue( int a ){// do something…}
　　D. public int addValue( int a, int b )throws MyException {//do something…}

3 Given: (5%)
Exhibit:
public class test {
public static void stringReplace (String text) {
text = text.replace (‘j’ , ‘i’);
}

public static void bufferReplace (StringBuffer text) {
text = text.append (“C”);
}

public static void main (String args[]} {
String textString = new String (“java”);
StringBuffer text BufferString = new StringBuffer (“java”);
stringReplace (textString);
bufferReplace (textBuffer);
System.out.printIn (textString + textBuffer);
}
}
What is the output