Which notation is preferred for expressing the volume of a gallon of milk in SI units?

The preferred notation for expressing the volume of a gallon of milk in SI units, specifically in liters, is 3.785 L. This value represents the equivalent of one U.S. gallon, which is the commonly used measurement for liquids in many contexts, including the volume of milk.

Understanding the conversion factors between gallons and liters is essential for precise measurements in scientific and technical contexts. One U.S. gallon is defined as approximately 3.785 liters, making this the correct conversion for the volume of milk. This correspondence ensures clarity and uniformity in scientific communication, particularly when working within the framework of the International System of Units (SI), which promotes the use of liters as the standard unit for volume.

The other values listed do not correspond to the volume of a gallon in either U.S. or UK measurements, which is why they are not applicable in this context.