public void Line_UnitVector()
        {
            Line testLine = new Line(Point.MakePointWithInches(2, 3, 1), Point.MakePointWithInches(5, -7, 0));
            Vector unitVector = testLine.UnitVector(new Inch());

            unitVector.Magnitude.Should().Be(new Distance(new Centimeter(), 2.54));
            unitVector.Direction.Should().Be(testLine.Direction);
            unitVector.BasePoint.Should().Be(testLine.BasePoint);
        }