Q1. Given the following two classes: 

How should you write methods in the ElectricAccount class at line n1 so that the member variable bill is always equal to the value of the member variable kwh multiplied by the member variable rate? 

Any amount of electricity used by a customer (represented by an instance of the customer class) must contribute to the customer's bill (represented by the member variable bill) through the method useElectricity method. An instance of the customer class should never be able to tamper with or decrease the value of the member variable bill. 

A. Option A 

B. Option B 

C. Option C 

D. Option D 

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Q2. Given the fragments: 

Which line causes a compilation error? 

A. Line n1 

B. Line n2 

C. Line n3 

D. Line n4 

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Q3. Which statement best describes encapsulation? 

A. Encapsulation ensures that classes can be designed so that only certain fields and methods of an object are accessible from other objects. 

B. Encapsulation ensures that classes can be designed so that their methods are inheritable. 

C. Encapsulation ensures that classes can be designed with some fields and methods declared as abstract. 

D. Encapsulation ensures that classes can be designed so that if a method has an argument MyType x, any subclass of MyType can be passed to that method. 

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Q4. Given the class definitions: 

And the code fragment of the main() method, 

What is the result? 

A. Java Java Java 

B. Java Jeve va 

C. Java Jeve ve 

D. Compilation fails 

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Q5. Given the code fragment: 

What is the result? 

A. 10 8 6 4 2 0 

B. 10 8 6 4 2 

C. AnArithmeticException is thrown at runtime 

D. The program goes into an infinite loop outputting: 10 8 6 4 2 0. . . 

E. Compilation fails 

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Q6. Which of the following can fill in the blank in this code to make it compile? 

A. abstract 

B. public 

C. default 

D. It will not compile with any as interfaces cannot have non abstract methods. 

E. It will compile without filling the blank. 

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Q7. Given: 

What is the result? 

A. Good Day! Good Luck! 

B. Good Day! Good Day! 

C. Good Luck! Good Day! 

D. Good Luck! Good Luck! 

E. Compilation fails 

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Q8. Given: 

public class FieldInit { 

char c; 

boolean b; 

float f; 

void printAll() { 

System.out.println("c = " + c); 

System.out.println("c = " + b); 

System.out.println("c = " + f); 

} 

public static void main(String[] args) { 

FieldInit f = new FieldInit(); 

f.printAll(); 

} 

} 

What is the result? 

A. c = null 

b = false 

f = 0.0F 

B. c = 0 

b = false 

f = 0.0f 

C. c = null 

b = true 

f = 0.0 

D. c = 

b = false 

f = 0.0 

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Q9. Given: 

And given the commands: 

javac Test.Java 

Java Test Hello 

What is the result? 

A. Success 

B. Failure 

C. Compilation fails. 

D. An exception is thrown at runtime 

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Q10. You are developing a banking module. You have developed a class named ccMask that has a maskcc method. 

Given the code fragment:

You must ensure that the maskcc method returns a string that hides all digits of the credit card number except the four last digits (and the hyphens that separate each group of four digits). 

Which two code fragments should you use at line n1, independently, to achieve this requirement? 

A. Option A 

B. Option B 

C. Option C 

D. Option D 

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