public override Length ConvertInS(Length S)
 {
     return(Length.Kilometer(S));
 }
 // km/Min
 public static VelocityInMeterPerMinute <Mag.Kilo> KilometerPerMinute(Length s, Time t)
 {
     return(KilometerPerMinute(Length.Kilometer(s).Vector / Time.Minutes(t).Value));
 }
 // km/h
 public static VelocityInKilometerPerHour KilometerPerHour(Length s, Time t)
 {
     return(KilometerPerHour(Length.Kilometer(s).Vector / Time.Hours(t).Value));
 }
 // km/s
 public static VelocityInMeterPerSec <Mag.Kilo> KilometerPerSec(Length s, Time t)
 {
     return(KilometerPerSec(Length.Kilometer(s).Vector / Time.Sec(t).Value));
 }