there are usually no requirements..
unless there is a quota for the maximum number of students allowed for a particular course because of a lack of teachersin that field..
prelim course for advanced
basic arithmetic and algebra
real functions
trig ratios
linear func
quad polyno and parbola
plane geo
tangent to a curve and derivative of a functio
hsc course for advanced
cooridnate meth in geo
applications of geo properies
geo appl. of differentiation...
mine are quite similar..never heard of a school making you do 13 units..
just doing ext1 english&maths, physics, legal studies, not sure if i wanna do eco though..
my approach..get the 100UAI (haha) then have fun selecting a course..