|≈||approximately equal to|
|digits||indicates that digits repeat infinitely (e.g. 8.294 369 corresponds to 8.294 369 369 369 369 …)|
The acre-foot is a unit of volume commonly used in the United States in reference to large-scale water resources, such as reservoirs, aqueducts, canals, sewer flow capacity, irrigation water, and river flows.
Traditional unit of piled firewood sold by volume. It typically measures a 4 x 1 x 4 foot stack and equals one-eights of a cord, 16 cubic feet, or 0.45 cubic meters.