public class ConversionTool {

    public static void main(String[] args){

    }

    public static float CentimetersToInches(float centimeters){
        if (centimeters >= 0){
            centimeters = centimeters * (float) 0.393701;

        }else{
            return 0;
        }
        return centimeters;
    }

    public static float InchesToCentimeters(float inches){
        if (inches >= 0){
            inches = inches * (float)2.54;
        }else{
            return 0;
        }
        return inches;
    }

    public static float FeetToMeters(float feet){
        if (feet > 0){
            feet = feet * (float)0.3048;
        }else{
            return 0;
        }
        return feet;
    }

    public static float MetersToFeet(float meters){
        if (meters > 0){
            meters = meters * (float)3.28084;
        }else{
            return 0;
        }
        return meters;
    }

    public static float CelsiusToFahrenheit(float celsius){
        if(celsius >= 0){
            celsius = (celsius) * (float)1.8 + 32;
        }
        return celsius;
    }

    public static float FahrenheitToCelsius(float fahrenheit){
        if (fahrenheit > 0){
            fahrenheit = (fahrenheit - 32) / (float)(1.8); 
        }
        return fahrenheit;
    }

    public static float MphToKph(float mph){
        if(mph > 0){
            mph = mph * (float)1.60934;
        }else{
            return 0;
        }
        return mph;
    }

    public static float KphToMph(float kph){
        if(kph > 0){
            kph = kph * (float)0.621371;
        }else{
            return 0;
        }
        return kph;
    }
}