internal void AtAltitude(Measurement <DistanceUnit> altitude, out double densityFactor, out Measurement <VelocityUnit> mach)
{
double a = altitude.In(DistanceUnit.Meter);
var t = CalculateTemperature(Temperature.In(TemperatureUnit.Kelvin), Altitude.In(DistanceUnit.Meter), a);
var p = CalculatePressure(Pressure.In(PressureUnit.Pascal), Temperature.In(TemperatureUnit.Kelvin), Altitude.In(DistanceUnit.Meter), a);
var d = CalculateDensity(t, p, Humidity);
densityFactor = d / StandartDensity1;
mach = new Measurement <VelocityUnit>(CalculateSoundVelocity(t), VelocityUnit.MetersPerSecond);
}
