public void AverageOfLengthsWithNullValueThrowsException()
{
var units = new IQuantity[] { Length.FromMeters(1), null };
Assert.Throws <NullReferenceException>(() => units.Average(LengthUnit.Centimeter));
}
public void AverageOfDifferentUnitsThrowsException()
{
var units = new IQuantity[] { Length.FromMeters(1), Volume.FromLiters(50) };
Assert.Throws <ArgumentException>(() => units.Average(LengthUnit.Centimeter));
}