The process of changing a program’s internal structure without changing the way the program works is _____________

Which statement is true? Select 3 options.

irina1246 [14]

Answer:

The statements which are true are;

A user-defined data type can include other user-defined data types

A user-defined data type is defined using a class

A user-defined data type can include a list

Explanation:

A user-defined data type (UDT) is a datatype that is defined and derived by the use of the datatypes which preexist including existing user-defined datatypes and the built-in datatypes

It is therefore true that a user-defined data type can include other user-defined data types

A class is a user-defined data type that contains both its member data and member functions, that can be used when an instance of the class is first created

Therefore, a user-defined data type is defined using a class

In a user-defined data type, a variable has actual data within it which can include an array or list

Therefore a user-defined data type can include a list.

3 0

2 years ago

Read 2 more answers

[1] Please find all the candidate keys and the primary key (or composite primary key) Candidate Key: _______________________ Pri

AVprozaik [17]

Answer:

Check the explanation

Explanation:

1. The atomic attributes can't be a primary key because the values in the respective attributes should be unique.

So, the size of the primary key should be more than one.

In order to find the candidate key, let the functional dependencies be obtained.

The functional dependencies are :

Emp_ID -> Name, DeptID, Marketing, Salary

Name -> Emp_ID

DeptID -> Emp_ID

Marketing -> Emp_ID

Course_ID -> Course Name

Course_Name -> Course_ID

Date_Completed -> Course_Name

Closure of attribute { Emp_ID, Date_Completed } is { Emp_ID, Date_Completed , Name, DeptID, Marketing, Salary, Course_Name, Course_ID}

Closure of attribute { Name , Date_Completed } is { Name, Date_Completed , Emp_ID , DeptID, Marketing, Salary, Course_Name, Course_ID}

Closure of attribute { DeptID, Date_Completed } is { DeptID, Date_Completed , Emp_ID,, Name, , Marketing, Salary, Course_Name, Course_ID}

Closure of attribute { Marketing, Date_Completed } is { Marketing, Date_Completed , Emp_ID,, Name, DeptID , Salary, Course_Name, Course_ID}.

So, the candidate keys are :

{ Emp_ID, Date_Completed }

{ Name , Date_Completed }

{ DeptID, Date_Completed }

{ Marketing, Date_Completed }

Only one candidate key can be a primary key.

So, the primary key chosen be { Emp_ID, Date_Completed }..

2.

The functional dependencies are :

Emp_ID -> Name, DeptID, Marketing, Salary

Name -> Emp_ID

DeptID -> Emp_ID

Marketing -> Emp_ID

Course_ID -> Course Name

Course_Name -> Course_ID

Date_Completed -> Course_Name

3.

For a relation to be in 2NF, there should be no partial dependencies in the set of functional dependencies.

The first F.D. is

Emp_ID -> Name, DeptID, Marketing, Salary

Here, Emp_ID -> Salary ( decomposition rule ). So, a prime key determining a non-prime key is a partial dependency.

So, a separate table should be made for Emp_ID -> Salary.

The tables are R1(Emp_ID, Name, DeptID, Marketing, Course_ID, Course_Name, Date_Completed)

and R2( Emp_ID , Salary)

The following dependencies violate partial dependency as a prime attribute -> prime attribute :

Name -> Emp_ID

DeptID -> Emp_ID

Marketing -> Emp_ID

The following dependencies violate partial dependency as a non-prime attribute -> non-prime attribute :

Course_ID -> Course Name

Course_Name -> Course_ID

So, no separate tables should be made.

The functional dependency Date_Completed -> Course_Name has a partial dependency as a prime attribute determines a non-prime attribute.

So, a separate table is made.

The final relational schemas that follows 2NF are :

R1(Emp_ID, Name, DeptID, Marketing, Course_ID, Course_Name, Date_Completed)

R2( Emp_ID , Salary)

R3 (Date_Completed, Course_Name, Course_ID)

For a relation to be in 3NF, the functional dependencies should not have any transitive dependencies.

The functional dependencies in R1(Emp_ID, Name, DeptID, Marketing, Date_Completed) is :

Emp_ID -> Name, DeptID, Marketing

This violates the transitive property. So, no table is created.

The functional dependencies in R2 ( Emp_ID , Salary) is :

Emp_ID -> Salary

The functional dependencies in R3 (Date_Completed, Course_Name, Course_ID) are :

Date_Completed -> Course_Name

Course_Name -> Course_ID

Here there is a transitive dependency as a non- prime attribute ( Course_Name ) is determining a non-attribute ( Course_ID ).

So, a separate table is made with the concerned attributes.

The relational schemas which support 3NF re :

R1(Emp_ID, Name, DeptID, Course_ID, Marketing, Date_Completed) with candidate key as Emp_ID.

R2 ( Emp_ID , Salary) with candidate key Emp_ID.

R3 (Date_Completed, Course_Name ) with candidate key Date_Completed.

R4 ( Course_Name, Course_ID ). with candidate keys Course_Name and Course_ID.

6 0

3 years ago

____ is the encapsulation of method details within a class.

Anestetic [448]

Implementation hiding i<u>s the encapsulation of method details within a class</u>. Implementation can be interpreted as those specifications which can be altered without altering the correctness of an application. Wrapping data/methods within classes (descriptions of the way all objects of this type will look/act) in combination with implementation hiding is called encapsulation. Information users need to know about behaviors should be available without dependence on implementation specifications.

6 0

3 years ago

To ____ a public member function of a base class in the derived class, the corresponding function in the derived class must have

Norma-Jean [14]

Answer:

None of the mentioned options

Explanation:

If we define a method in a derived class with same declaration type as that of base class then it is said to be overriding a function which behaves differently which will depend on the object which is calling the method.
Option a,b and c are not any kind of methods we implement using coding.
Option d is done when number or data types of parameters are different than the declaration of the base type.

8 0

3 years ago

Define function print_popcorn_time() with parameter bag_ounces. If bag_ounces is less than 3, print "Too small". If greater than

Gnoma [55]

Answer:

public static void print_popcorn_time(int bag_ounces){

if(bag_ounces<3){

System.out.println("Too Small");

}

else if(bag_ounces>10){

System.out.println("Too Large");

}

else{

bag_ounces*=6;

System.out.println(bag_ounces+" seconds");

}

Explanation:

Using Java prograamming Language.

The Method (function) print_popcorn_time is defined to accept a single parameter of type int

Using if...else if ....else statements it prints the expected output given in the question

A complete java program calling the method is given below

public class num6 {

public static void main(String[] args) {

int bagOunces = 7;

print_popcorn_time(bagOunces);

}

public static void print_popcorn_time(int bag_ounces){

if(bag_ounces<3){

System.out.println("Too Small");

}

else if(bag_ounces>10){

System.out.println("Too Large");

}

else{

bag_ounces*=6;

System.out.println(bag_ounces+" seconds");

}

3 0

3 years ago

The process of changing a program’s internal structure without changing the way the program works is ______________.