I am trying to make a button that goes into another activity but every time I press it the app crashes
Here is the code from my `MainActivity.java` file:

```
package com.example.noot_a_normal_pc.kmtomiles;

import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
import static android.widget.Toast.makeText;

public class MainActivity extends AppCompatActivity implements View.OnClickListener {

    Button buttonBegin, buttonExit;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        buttonBegin = (Button) findViewById(R.id.begin);
        buttonBegin.setOnClickListener(this);
        buttonExit = (Button) findViewById(R.id.exit);
        buttonExit.setOnClickListener(this);
    }

    @Override
    public void onClick(View v) {
        if (v.equals(buttonExit)) {
            Toast.makeText(getApplicationContext(), "Why would you want to exit such a great app?", Toast.LENGTH_LONG).show();
        }
        else if (v.equals(buttonBegin)) {
            Intent intent = new Intent (this, question.class);
            startActivity(intent);
        }
    }

}

```

Here is the code for both of my buttons from my XML file:

```
<Button
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Begin"
    android:id="@+id/begin"
    android:layout_marginTop="45dp"
    android:layout_below="@+id/textView"
    android:layout_alignRight="@+id/textView"
    android:layout_alignEnd="@+id/textView"
    android:clickable="true"
    android:background="#ffffff"/>

<Button
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Exit"
    android:id="@+id/exit"
    android:layout_marginTop="27dp"
    android:layout_below="@+id/begin"
    android:layout_alignLeft="@+id/begin"
    android:layout_alignStart="@+id/begin"
    android:clickable="true"
    android:background="#ffffff" />

```

Here is my stacktrace message:

```
7-2477/? E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.noot_a_normal_pc.kmtomiles, PID: 2477
android.content.ActivityNotFoundException: Unable to find explicit activity class {com.example.noot_a_normal_pc.kmtomiles/com.example.noot_a_normal_pc.kmtomiles.question}; have you declared this activity in your AndroidManifest.xml?
 at android.app.Instrumentation.checkStartActivityResult(Instrumentation.java:1794)
 at android.app.Instrumentation.execStartActivity(Instrumentation.java:1512)
 at android.app.Activity.startActivityForResult(Activity.java:3917)
 at android.app.Activity.startActivityForResult(Activity.java:3877)
 at android.support.v4.app.FragmentActivity.startActivityForResult(FragmentActivity.java:842)
 at android.app.Activity.startActivity(Activity.java:4200)
 at android.app.Activity.startActivity(Activity.java:4168)
 at com.example.noot_a_normal_pc.kmtomiles.MainActivity.onClick(MainActivity.java:33)
 at android.view.View.performClick(View.java:5198)
 at android.view.View$PerformClick.run(View.java:21147)
 at android.os.Handler.handleCallback(Handler.java:739)
 at android.os.Handler.dispatchMessage(Handler.java:95)
 at android.os.Looper.loop(Looper.java:148)
 at android.app.ActivityThread.main(ActivityThread.java:5417)
 at java.lang.reflect.Method.invoke(Native Method)
 at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
 at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)

```