Your assignment is to write a menu driven program. The menu will be responded to using a switch statement. The menu options (cases) will be as follows (You should give them more succinct labels in your program): Read the user’s first name and echo it back out 20 times. Read the user’s age and double it and display the age and the doubled age. Read the user's age and output one of the following statements: Since you are xx years old, you are a teenager Since you are xx years old, you are NOT a teenager (***of course xx displays the user's age) Read a single integer between 3 and 50 from the user. Create a triangle of X’s with the as many rows as the value of the user's input. The triangle needs to be displayed on the screen and in a text document named triangle. txt.

Explanation:

import java.util.Scanner;

public class Menu {

  public static void main(String[] args) {

      /*

      * Creating an Scanner class object which is used to get the inputs

      * entered by the user

      */

      Scanner sc = new Scanner(System.in);

      int choice;

do

{

  System.out.println("\n::MENU::");

      System.out.println("1.Echo Name");

      System.out.println("2.Double Your Age");

      System.out.println("3.Check Teenager or not");

      System.out.println("4.Display Triangle");

      System.out.println("5.Exit");

      System.out.print("Enter Choice:");

      choice = sc.nextInt();

      switch (choice) {

      case 1: {

          System.out.print("Enter your name");

          String name=sc.nextLine();

          for(int i=1;i<=20;i++)

          {

              System.out.println(name);

          }

          break;

      }

      case 2: {

          int age;

          System.out.print("Enter age :");

          age=sc.nextInt();

          System.out.println("Your age :"+age);

          System.out.println("Doubled age :"+(2*age));

          break;

      }

      case 3: {

          int age;

          System.out.print("Enter age :");

          age=sc.nextInt();

          if(age>=13 && age<=19)

          {

              System.out.println("Since you are "+age+" years old.Your are a Teenager");

          }

          else

          {

              System.out.println("Since you are "+age+" years old.Your are not a Teenager");

          }

          break;

      }

      case 4: {

          int rows;

          do

          {

          System.out.print("Enter a number (between 3 and 50):");

          rows=sc.nextInt();

          if(rows<3 || rows>50)

          {

              System.out.println("** Invalid.Must be between 3 and 50 **");

          }

          }while(rows<3 || rows>50);

          printTriangle(rows);

          break;

      }

      case 5:{

          break;

      }

      default: {

          System.out.println("** Invalid Choice **");

          break;

      }

      }  

}while(choice!=5);

  }

  private static void printTriangle(int size) {

      char ch='*';

      for (int a = 0; a < 2 * size - 1; a++) {

          if (a % 2 == 0) {

              for (int b = 0; b < (2 * size - 1) - a; b++) {

                  System.out.print(" ");

              }

              for (int c = 0; c <= a; c++) {

                  System.out.print(ch+" ");

              }

              System.out.println();

          }

      }

  }

}

Output:

::MENU::

1.Echo Name

2.Double Your Age

3.Check Teenager or not

4.Display Triangle

5.Exit

Enter Choice:1

Enter your name: Mirian

Mirian

Mirian

Mirian

Mirian

Mirian

Mirian

Mirian

Mirian

Mirian

Mirian

Mirian

Mirian

Mirian

Mirian

Mirian

Mirian

Mirian

Mirian

Mirian

Mirian

::MENU::

1.Echo Name

2.Double Your Age

3.Check Teenager or not

4.Display Triangle

5.Exit

Enter Choice:2

Enter age :23

Your age :23

Doubled age :46

::MENU::

1.Echo Name

2.Double Your Age

3.Check Teenager or not

4.Display Triangle

5.Exit

Enter Choice:3

Enter age :16

Since you are 16 years old.Your are a Teenager

::MENU::

1.Echo Name

2.Double Your Age

3.Check Teenager or not

4.Display Triangle

5.Exit

Enter Choice:4

Enter a number (between 3 and 50):6

*

* * *

* * * * *

* * * * * * *

* * * * * * * * *

* * * * * * * * * * *

::MENU::

1.Echo Name

2.Double Your Age

3.Check Teenager or not

4.Display Triangle

5.Exit

Enter Choice:5

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explanation: