South Australia contains 324 separate Protected Areas with a total land area of 21,630,995 hectares(21.97% of the state’s area). 18 of these are National parks, totalling 4,337,430 hectares (4.41% of the state’s area).
... the formula should be understood as "either of those element(s) of the field whose square equals b2 - 4ac". In some fields, some elements have no ...