US fluid ounce (fl oz)
Definition: US fluid ounce na 1/128 of US gallon, about 29.5735 milliliters.
History/origin: US fluid ounce come from old English systems and remain tied to US gallon after US and imperial systems split.
Current use: US fluid ounces dey used for United States on drink cans, nutrition labels, recipes, and personal care products.
Cubic kilometer (km³)
Definition: Cubic kilometer na huge metric volume unit. One 1 km × 1 km × 1 km cube get 1,000,000,000 m³, or 1,000,000,000,000 L.
History/origin: Earth science need readable unit for very big natural volumes, so km³ help for water bodies, ice, rock, magma, and atmosphere-scale quantities.
Current use: km³ dey show for hydrology, climate reports, ocean volume estimates, glacier studies, volcanic eruption data, reservoir capacity, and large-scale geography.