rest wiki:
[ has several different meanings. See:rest (music), a pause in a piece of music.rest (object), a support for a musket or billiards or snooker cue.rest (physics), the relation between two observers.rest as action, to relax, see recreation.The reserves of the Bank of England.In software engineering, REST is an acronym for Representational State Transfer.ReST also refers to the markup language, ReStructuredText.In chemistry a rest (abbreviated R) is a variable part of a molecule attached to a given core structure. See: Functional group and side chain.
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gravel wiki:
is rock that is of a certain size range. In geology, gravel is any loose rock that is at least two millimeters in its largest dimension (about 1/12 of an inch), and no more than 75 millimeters (about 3 inches). Sometimes gravel is restricted to rock in the 2-4 millimeter range, with pebble being reserved for rock 4-75 millimeters (some say 64 millimeters). The next smaller size class in geology is sand, which is 0.02 mm to 2 mm in size. The next larger size is cobble, which is 75 (64) millimeters to 256 millimeters (about ten inches).
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