31. What is the stored in the object obj in following lines of code?
    

    
    box obj;
    

1. 1. Any arbitrary pointer

   
   
   

   2. Memory address of allocated memory of object

   
   
   

   3. Garbage

   
   
   

   4. NULL

   
   
   

   5. None of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   Memory is allocated to an object using new operator. box obj; just declares a reference to object, no memory is allocated to it hence it points to NULL.

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32. Which of these class contains only floating point functions?

1. 1. Object

   
   
   

   2. System

   
   
   

   3. Process

   
   
   

   4. Math

   
   
   

   5. None of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   Math class contains all the floating point functions that are used for geometry, trigonometry, as well as several general purpose methods. Example : sin(), cos(), exp(), sqrt() etc.

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33. Which of these methods is called when observed object has changed?

1. 1. notifyObserver()

   
   
   

   2. update()

   
   
   

   3. setChanged()

   
   
   

   4. All of above

   
   
   

   5. None of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   notifyObserver(), update(), setChanged().

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34. Which of these methods is used to notify observer the change in observed object?

1. 1. notify()

   
   
   

   2. update()

   
   
   

   3. observed()

   
   
   

   4. check()

   
   
   

   5. None of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: A

   update()

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35. What is the use of Observable class?

1. 1. It is used to create classes that can be accessed by other parts of program

   
   
   

   2. It is used to create methods that can be accessed by other parts of program

   
   
   

   3. It is used to create global subclasses

   
   
   

   4. It is used to create classes that other part of the program can observe

   
   
   

   5. None of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   The Observable class is used to create subclasses that other part of program can observe.

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