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).
... Generalizations
The formula and its proof remain correct if the coefficients a, b and c are complex numbers, or more generally members of any field ...