// Conversion methods 	
	
public class Conversion {	
	// conversion equivalencies	
	private static final double KILOMETERS_PER_MILE = 1.609344;	
	private static final double LITERS_PER_GALLON = 3.785411784;	
	private static final double GRAMS_PER_OUNCE = 28.349523125;	
	private static final double HECTARES_PER_ACRE = 0.40468564;	
	
	// temperature conversions methods	
	public static double fahrenheitToCelsius(double fahrenheit) {	
		return (fahrenheit - 32) / 1.8;	
	}	
	
	public static double celsiusToFahrenheit(double celsius) {	
		return 1.8 * celsius + 32;	
	}	
	
	// length conversions methods	
	public static double kilometersToMiles(double kilometers) {	
		return kilometers / KILOMETERS_PER_MILE;	
	}	
	
	public static double milesToKilometers(double miles) {	
		return miles * KILOMETERS_PER_MILE;	
	}	
	
	// mass conversions methods	
	public static double litersToGallons(double liters) {	
		return liters / LITERS_PER_GALLON;	
	}	
	
	public static double gallonsToLiters(double gallons) {	
		return gallons * LITERS_PER_GALLON;	
	}	
	
	public static double gramsToOunces(double grams) {	
		return grams / GRAMS_PER_OUNCE;	
	}	
	
	public static double ouncesToGrams(double ounces) {	
		return ounces * GRAMS_PER_OUNCE;	
	}	
	
	// area conversions methods	
	public static double hectaresToAcres(double hectares) {	
		return hectares / HECTARES_PER_ACRE;	
	}	
	
	public static double acresToHectares(double acres) {	
		return acres * HECTARES_PER_ACRE;	
	}	
}