Force Close on Activity Switch
<p>I'm using a button to switch activities, but logcat says that I havent declared the activity in my <code>AndroidManifest.xml</code> Ive checked at least five times, and it is in there. 
Im trying to switch to the fahrenheittocelsius class.</p>

<p>My main java page with the button is here:</p>

<pre><code>package com.jordandebarth.supercalculator;


import com.jordandebarth.supercalculator.distance;
import com.jordandebarth.supercalculator.exponents;
import com.jordandebarth.supercalculator.nuclearfusion;
import com.jordandebarth.supercalculator.pythagorean;
import com.jordandebarth.supercalculator.fahrenheittocelsius;

import android.os.Bundle;
import android.app.Activity;
import android.content.Intent;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.support.v4.app.NavUtils;


public class tab_view extends Activity {

    Button calculator, pythagorean, distance, exponent, temperature, nuclearfusion;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_tab_view);
        calculator = (Button)findViewById(R.id.calculatorButton);
        pythagorean = (Button)findViewById(R.id.pythagoreanButton);
        distance = (Button)findViewById(R.id.distanceButton);
        exponent = (Button)findViewById(R.id.exponentsButton);
        temperature = (Button)findViewById(R.id.temperatureButton);
        nuclearfusion = (Button)findViewById(R.id.nuclearfusion);


        pythagorean.setOnClickListener(new View.OnClickListener() {

            public void onClick(View v) {
                // TODO Auto-generated method stub
                Intent pythagoreanIntent = new Intent(getBaseContext(), pythagorean.class);
                startActivityForResult(pythagoreanIntent, 0);
                overridePendingTransition(R.anim.slide_in_right, R.anim.slide_out_left);
            }
        });
        distance.setOnClickListener(new View.OnClickListener() {

            public void onClick(View v) {
                // TODO Auto-generated method stub
                Intent distanceIntent = new Intent(getBaseContext(), distance.class);
                startActivityForResult(distanceIntent, 0);
                overridePendingTransition(R.anim.slide_in_right, R.anim.slide_out_left);
            }
        });
        exponent.setOnClickListener(new View.OnClickListener() {

            public void onClick(View v) {
                // TODO Auto-generated method stub
                Intent exponentIntent = new Intent(getBaseContext(), exponents.class);
                startActivityForResult(exponentIntent, 0);
                overridePendingTransition(R.anim.slide_in_right, R.anim.slide_out_left);
            }
        });
        temperature.setOnClickListener(new View.OnClickListener() {

            public void onClick(View v) {
                // TODO Auto-generated method stub
                Intent temperatureIntent = new Intent(getBaseContext(), fahrenheittocelsius.class);
                startActivityForResult(temperatureIntent, 0);
                overridePendingTransition(R.anim.slide_in_right, R.anim.slide_out_left);
            }
        });
        nuclearfusion.setOnClickListener(new View.OnClickListener() {

            public void onClick(View v) {
                // TODO Auto-generated method stub
                Intent nuclearfusionIntent = new Intent(getBaseContext(), nuclearfusion.class);
                startActivityForResult(nuclearfusionIntent, 0);
                overridePendingTransition(R.anim.slide_in_right, R.anim.slide_out_left);
            }
        });

    }




}
</code></pre>

<p>and my AndroidManifest is:</p>

<pre><code>&lt;manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.jordandebarth.supercalculator"
    android:versionCode="1"
    android:versionName="1.0" &gt;

    &lt;uses-sdk
        android:minSdkVersion="8"
        android:targetSdkVersion="15" /&gt;

    &lt;application
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" &gt;
        &lt;activity
            android:name=".tab_view"
            android:label="@string/title_activity_tab_view" &gt;
            &lt;intent-filter&gt;
                &lt;action android:name="android.intent.action.MAIN" /&gt;

                &lt;category android:name="android.intent.category.LAUNCHER" /&gt;
            &lt;/intent-filter&gt;
        &lt;/activity&gt;
       &lt;activty
            android:name=".fahrenheittocelsius"
            android:label="Fahrenheit to Celsius"
            &gt;&lt;/activty&gt;

        &lt;activity
            android:name=".calculator"
            android:label="Calculator"  &gt;
        &lt;/activity&gt;
        &lt;activity
            android:name=".pythagorean"
            android:label="Pythagorean Theorem"
            &gt;

        &lt;/activity&gt;
        &lt;activity
            android:name=".distance"
            android:label="Distance Formula"
            &gt;&lt;/activity&gt;
        &lt;activity 
            android:name=".exponents"
            android:label="Exponents"
            &gt;&lt;/activity&gt;

        &lt;activity
            android:name=".nuclearfusion"
            android:label="Nuclear Fusion"
            &gt;&lt;/activity&gt;
    &lt;/application&gt;


&lt;/manifest&gt;
</code></pre>
