Question Discussion & Solution

• The Best example of Run time polymorphism is Function Overriding
• Function Overloading is the example of Compile time polymorphism
• Protected is an Access modifier  

Important Point

Compile-time polymorphism

It means binding is occurring at compile time It can be achieved through static binding. If a class has multiple methods having the same name but different in parameters, it is known as Method Overloading.

Run time polymorphism

At run time we came to know which method is going to invoke It can be achieved through dynamic binding. If subclass (child class) has the same method as declared in the parent class, it is known as method overriding

Access Modifiers

It specifies the accessibility or scope of a field, method, constructor, or class. There are three types of Access modifiers

• Public: The methods or data members that are declared as public can be accessed anywhere in the program.
• Private:  The methods or data members declared as private are accessible only within the class in which they are declared.
• Protected: The methods or data members declared as protected can accessible within the same class or class which is inherited from it.

The logic followed here is:

'Thermometer' is used to measure 'temperatures'.

Similarly,

An 'anemometer' is a device used for measuring 'Wind' speed.

The correct answer is Concave.

• Myopia: A person suffering from myopia can see the near objects clearly while far objects are not clear.
  • A Concave lens (diverging lens) is used by people suffering from myopia.

Additional Information

• Hypermetropia: A person suffering from hypermetropia can see distant objects clearly but not near objects.
  • People suffering from hypermetropia uses a Convex lens.
• Astigmatism: This defect arises due to the difference in the radius of curvature of the cornea in the different planes
  • The cylindrical lens is used by people suffering from Astigmatism.

The pattern followed here is:

Hence, '41' is the correct answer.

The correct answer is Primary key.

Key Points

• The foreign key is not necessarily the primary key in its current table.
  • It only has to contain the same information that is held in another table’s primary key.
  • Foreign keys are the columns of a table that points to the primary key of another table. They act as a cross-reference between tables.

Additional Information​ 

• A report generator is a computer program whose purpose is to take data from a source such as a database, XML stream or a spreadsheet, and use it to produce a document in a format which satisfies a particular human readership.
• The data dictionary is a set of information describing the contents, format, and structure of a database and the relationship between its elements, used to control access to and manipulation of the database.
• Schema objects are logical structures created by users. Objects such as tables or indexes hold data or can consist of a definition only, such as a view or synonym.