Given：
22.StringBuilder sb1 = new StringBuilder（"123"）；
23.String s1 = "123"；
24.// insert code here
25.System.out.println（sb1 + " " + s1）；
Which code fragment， inserted at line 24， outputs "123abc 123abc"？（）
A.sb1.append（"abc"）； s1.append（"abc"）；
B.sb1.append（"abc"）； s1.concat（"abc"）；
C.sb1.concat（"abc"）； s1.append（"abc"）；
D.sb1.concat（"abc"）； s1.concat（"abc"）；
E.sb1.append（"abc"）； s1 = s1.concat（"abc"）；
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Given：
Which method will complete this class？（）
A.public int compareTo（Object o）{/*more code here*/}
B.public int compareTo（Score other）{/*more code here*/}
C.public int compare（Score s1，Score s2）{/*more code here*/}
D.public int compare（Object o1，Object o2）{/*more code here*/}
Given：
What is the result？（）
A.test end
B.Compilation fails.
C.test runtime end
D.test exception end
E.A Throwable is thrown by main at runtime.
Given that the current directory is empty， and that the user has read and write permissions， and thefollowing：
Which statement is true？（）
A.Compilation fails.
B.The file system has a new empty directory named dir.
C.The file system has a new empty directory named newDir.
D.The file system has a directory named dir， containing a file f1.txt.
E.The file system has a directory named newDir， containing a file f1.txt.
A.Closing an open stream.
B.Flushing an open stream.
C.Writing to an open stream.
D.Writing a line separator to an open stream.
Given:
What is the output?（）
A.42
B.420
C.462
D.42042
Given：
11.double input = 314159.26；
12.NumberFormat nf = NumberFormat.getInstance（Locale.ITALIAN）；
13.String b；
14.//insert code here
Which code， inserted at line 14， sets the value of b to 314.159，26？（）
A.b = nf.parse（ input ）；
B.b = nf.format（ input ）；
C.b = nf.equals（ input ）；
D.b = nf.parseObject（ input ）；
Given a valid DateFormat object named df，and
16.Date d = new Date（0L）；
17.String ds = "December 15， 2004"；
18.//insert code here
What updates d’s value with the date represented by ds？（）
A.18. d = df.parse（ds）；
B.18. d = df.getDate（ds）；
C.18. try {19. d = df.parse（ds）；20. } catch（ParseException e） { }；
D.18. try {19. d = df.getDate（ds）；20. } catch（ParseException e） { }；
Assuming that the serializeBanana（） and the deserializeBanana（） methods will correctly use Javaserialization and given：
What is the result？（）
A.restore 400
B.restore 403
C.restore 453
D.Compilation fails.
E.An exception is thrown at runtime.
Given：
What is the result？（）
A.Canada
B.null Canada
C.Canada null
D.Canada Canada
E.Compilation fails due to an error on line 26.
A team of programmers is reviewing a proposed API for a new utility class. After some discussion， theyrealize that they can reduce the number of methods in the API without losing any functionality.
If theyimplement the new design，which two OO principles will they be promoting？（）
A.Looser coupling
B.Tighter coupling
C.Lower cohesion
D.Higher cohesion
E.Weaker encapsulation
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Click the Exhibit button.What two must the programmer do to correct the compilation errors？（）
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Click the Exhibit button.Which graph represents the correct directory structure for a JAR file from which those classes can be used by the compiler and JVM？（）
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Given：Which code fragment， inserted at the end of line 12， produces the output p is 420？（）
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