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I am trying to implement the calculations, and I am getting totally wrong answers. This program is to calculate the distance of a projectile based on launch angles as well as (of course) launch velocities(speeds). The formula is as follows: http://learn.flvs.net/webdav/educator_apcsa_v8/module09/rtfmod09/09_04_VirtualLectureNotes.pdf

Here is the code that I have for doing the calculations:

```
/**
* This purpose of this program is to calculate the trajectory of a projectile based on launch angles and launch velocities.
*
* @author John D. Barry
* @version 03/24/09
*/
class Catapult
{
//declaration of private instance variables
private int launchSpeed;
private double distance, distanceInFeet, launchAngle, calculateAngleLaunch;
//constructor for ojbects of type CO2Footprint
Catapult(int theLaunchSpeed, double theLaunchAngle)
{
launchSpeed = theLaunchSpeed;
launchAngle = theLaunchAngle;
}
//mutator method to calculate the the distance
public void calcDistance()
{
distance = (Math.pow(launchSpeed,2) * Math.sin(launchAngle * 2)) / 9.8;
}
//mutator method to calculate the distance in feet
public void calcDistanceInFeet()
{
distanceInFeet = (distance * 100) / 2.54 * 12;
}
//getter method to get the value of the distance in feet
public double getDistanceInFeet()
{
return distanceInFeet;
}
}
```

```
/**
* This class tests the Catapult class.
*
* @author John D. Barry
* @version 03/24/09
*/
import java.util.ArrayList;
public class CatapultTester
{
public static void main(String[] args)
{
ArrayList<Catapult> catapult = new ArrayList<Catapult>();
catapult.add(new Catapult(40,25));
catapult.add(new Catapult(20,30));
catapult.add(new Catapult(20,35));
catapult.add(new Catapult(20,40));
catapult.add(new Catapult(20,45));
catapult.add(new Catapult(20,50));
catapult.add(new Catapult(20,55));
Catapult catapultRecord; //creates a new catapultRecord object of type Catapult
for(int index = 0; index < catapult.size(); index++)
{
catapultRecord = catapult.get(index);
catapultRecord.calcDistance();
catapultRecord.calcDistanceInFeet();
}
System.out.println(" Projectile Distance (feet) ");
System.out.println(" MPH 25 deg 30 deg 35 deg 40 deg 45 deg 50 deg");
System.out.println("=================================================================================================================");
for(int index = 0; index < catapult.size(); index++)
{
catapultRecord = catapult.get(index);
System.out.printf("%12.2f",catapultRecord.getDistanceInFeet());
}
}
}
```

For example, I know that the first problem should equal 410 feet and by the program calculation it is showing: -2065.08

So.... ...something is wrong here I just don't know what!!