- published: 16 Aug 2016
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An 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.
As the name suggests, an acre-foot is defined as the volume of one acre of surface area to a depth of one foot.
Since an acre is defined as a chain by a furlong (i.e. 66 ft × 660 ft), an acre-foot is 43,560 cubic feet (1,233 m3).
There are two definitions of an acre-foot (differing by about 0.0006%), depending on whether the "foot" used is an "international foot" or a "U.S. survey foot.
As a rule of thumb in U.S. water management, one acre-foot is taken to be the planned water usage of a suburban family household, annually. In some areas of the desert Southwest, where water conservation is followed and often enforced, a typical family uses only about 0.25 acre-feet of water per year. One acre-foot/year is approximately 893 gallons (3.38 m³) per day.
The acre-foot (or more specifically the time rate unit of acre-foot per year) has been used historically in the U.S. in many water-management agreements, for example the Colorado River Compact, which divides 15 million acre-feet (MAF) per year or (586 m³/s) among seven western U.S. states.
The acre is a unit of land area used in the imperial and US customary systems. It is defined as the area of 1 chain (22 yards) by 1 furlong (220 yards), which is exactly equal to 1⁄640 of a square mile, 43,560 square feet, approximately 4,047 m2, or about 40% of a hectare.
The acre is commonly used in Antigua and BarbudaAustralia, American Samoa,The Bahamas,Belize, the British Virgin Islands, the Cayman Islands,Canada,Dominica, the Falkland Islands,Grenada,Ghana, Guam, the Northern Mariana Islands,India, Ireland, Jamaica,Montserrat,Myanmar, Pakistan, Samoa,St. Lucia,St. Helena,St. Kitts and Nevis,St. Vincent and the Grenadines,Turks and Caicos, the United Kingdom, the United States and the US Virgin Islands.
The international symbol of the acre is ac. The most commonly used acre today is the international acre. In the United States both the international acre and the slightly different US survey acre are in use. The most common use of the acre is to measure tracts of land. One international acre is defined as exactly 4,046.8564224 square metres.
The foot (plural feet) is an anatomical structure found in many vertebrates. It is the terminal portion of a limb which bears weight and allows locomotion. In many animals with feet, the foot is a separate organ at the terminal part of the leg made up of one or more segments or bones, generally including claws or nails.
The human foot is a strong and complex mechanical structure containing 26 bones, 33 joints (20 of which are actively articulated), and more than a hundred muscles, tendons, and ligaments. The joints of the foot are the ankle and subtalar joint and the interphalangeal articulations of the foot.
An anthropometric study of 1197 North American adult Caucasian males (mean age 35.5 years) found that a man's foot length was 26.3 cm with a standard deviation of 1.2 cm.
The foot can be subdivided into the hindfoot, the midfoot, and the forefoot:
The hindfoot is composed of the talus (or ankle bone) and the calcaneus (or heel bone). The two long bones of the lower leg, the tibia and fibula, are connected to the top of the talus to form the ankle. Connected to the talus at the subtalar joint, the calcaneus, the largest bone of the foot, is cushioned inferiorly by a layer of fat.
Break through depression from inside
Lost hope seems to be a state of mind
Can't stand it, hate the way I feel
Forced to dream of things that are surreal
Living hell
Can't subside
Fear existence
Count the reasons why
Put to death, my mortal soul
Heaven help me, my blood flows thin and cold
Race insanity, walk the line
Bad impression seen through selfish eyes
Abstain repression when it's useless to resist
The main objective is to sever thought being sane
Frustration, anger think about the cause
Fight a fight within yourself can't let the feeling go
An answer must be figured out to keep the system strong
An uncontrolled desire to dominate the soul
Little by little memories go bleak
The price you pay, the words you say a steady flow you seek
When time stands still give a little shove