Is God willing to prevent evil, but not able? Then he is not omnipotent. Is he able, but not willing? Then he is malevolent. Is he both able and willing? Then whence cometh evil? Is he neither able nor willing? Then why call him God?
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'''Ridge roughness''' (named ''K factor'' in the [[Wind erosion equation]] ) is - according to the [[USDA]] terminology - ''"a measure of the effect of ridges made by tillage and planting implements. It is expressed as a decimal from 0.5 to 1.0. ''
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''Ridges, especially those at right angles to the prevailing wind direction, absorb and deflect wind energy and trap moving [[soil]] particles."<ref>[http://www.nrcs.usda.gov/technical/NRI/1997/summary_report/glossary.html List of USDA terminology]</ref>''