NEED HELP WITH JAVA ERROR

QUESTIOIN.JAVA

package questionsapp;

import java.util.Scanner;

$/**$

$*$ A question with a text and an answer.

$*/$

public class Question $\{$

private String text;

private String answer;

$/**$

$*$ Constructs a question with empty question and answer.

$*/$

public Question$()\{$

text $=""$;

answer $=""$;

$\}$

$/**$

$*$ Sets the question text.

$*$

$*$ @param questionText the text of this question

$*/$

public void setText$($String questionText$)\{$

text $=$ questionText;

$\}$

$/**$

$*$ Sets the answer for this question.

$*$

$*$ @param correctResponse the answer

$*/$

public void setAnswer$($String correctResponse$)\{$

answer $=$ correctResponse;

$\}$

$/**$

$*$ Checks a given response for correctness.

$*$

$*$ @param response the response to check

$*$ @return true if the response was correct, false otherwise

$*/$

public boolean checkAnswer$($String response$)\{$

return response.equals$($answer$)$;

$\}$

$/**$

$*$ Displays this question.

$*/$

public void display$()\{$

System.out.println$($text$)$;

$\}$

public class NumericQuestion extends Question

$\{$

double answer;

$//$ constructor

public NumericQuestion$()\{$

super$()$;

$\}$

$//$ sets the correct answer

public void setAnswer$($double correctResponse$)\{$

answer $=$ correctResponse;

$\}$

$/**$

$*$ Checks a given response for correctness.

$*$

$*$ @param response the response to check

$*$ @return true if the response was $<=0\mathrm{.}01$ correctness, false otherwise

$*/$

@Override

public boolean checkAnswer$($String response$)\{$

double givenanswer $=$ Double.parseDouble$($response$)$;

return Math.abs$($givenanswer $-$ answer$)<=0\mathrm{.}01$;

$\}$

$\}$

public class FillInQuestion extends Question $\{$

$//$ default constructor

public FillInQuestion$()\{$

super$()$;

$\}$

$/**$

$*$ Sets the question text.

$*$

$*$ @param questionText the text of this question

$*/$

@Override

public void setText$($String questionText$)\{$

Scanner scanner $=$ new Scanner$($questionText$)$;

$//$ spliting the string using the delimiter

scanner.useDelimiter$("\_")$;

$//$ taking first part into question

String question $=$ scanner.next$()$;

$//$ taking another part to answer

String answer $=$ scanner.next$()$;

$//$ appending delimiter to the question

question $+="\_\_\_"$;

$//$ closing the scanner object

scanner.close$()$;

$//$ setting the question and answer of the question class

super.setText$($question$)$;

super.setAnswer$($answer$)$;

$\}$

$\}$

$\}$

QUESTIONSAPP.JAVA

package questionsapp;

import java.util.Scanner;

import java.util.ArrayList;

public class QuestionsApp $\{$

public static void main$($String$[]$ args$)\{$

ArrayList Questions $=$ new ArrayList$()$;

int totalScore $=0$;

NumericQuestion n$1=$ new NumericQuestion$()$;

n$1.$setText$("$What is the value of PI to the nearest thousandth?"$)$;

n$1.$setAnswer$(3\mathrm{.}141)$;

Questions.add$($n$1)$;

NumericQuestion n$2=$ new NumericQuestion$()$;

n$2.$setText$("$What is the value of the Euler's number to the nearest thousandth?"$)$;

n$2.$setAnswer$(2\mathrm{.}718)$;

Questions.add$($n$2)$;

FillInQuestion f$1=$ new FillInQuestion$()$;

f$1.$setText$("$The inventor of Java was $\_$James Gosling$\_")$;

Questions.add$($f$1)$;

FillInQuestion f$2=$ new FillInQuestion$()$;

f$2.$setText$("$The inventor of Pascal was $\_$Niklaus Wirth$\_")$;

Questions.add$($f$2)$;

for $($Question q : Questions$)\{$

boolean isCorrect $=$ presentQuestion$($q$)$;

if $($isCorrect$)\{$

System.out.println$("$Correct answer :$)$

$")$;

if $($q instanceof NumericQuestion$)\{$

totalScore $+=1$;

$\}$

if $($q instanceof FillInQuestion$)\{$

totalScore $+=2$;

$\}$

$\}$ else $\{$

System.out.println$("$Wrong answer :$($

$")$;

$\}$

$\}$

System.out.printf$("$Total score is $\%$d out of $\%$d

Thank You!

$",$ totalScore, $12)$;

$\}$

$/**$

$*$ Presents a question to the user and checks the response.

$*$

$*$ @param q the question

$*/$

public static boolean presentQuestion$($Question q$)\{$

q$.$display$()$;

System.out.print$("$Your answer: $")$;

Scanner in $=$ new Scanner$($System$.$in$)$;

String response $=$ in$.$nextLine$()$;

return q$.$checkAnswer$($response$)$;

$\}$

$\}$

THIS IS THE ERROR

error: cannot find symbol

NumericQuestion n$1=$ new NumericQuestion$()$;

symbol: class NumericQuestion

location: class QuestionsApp