I think Dillon's half-right, but it's been a while and I suppose things may have changed.
Mac takes marks from grade 12 Chem, Physics, Calc and Vectors, and English.
This leaves you with two bird spots. If you're going into Engineering, it's more likely than not that Advanced Functions is one of these but there's nothing saying that it
has to be. It's a prereq for Calc and Vectors anyway, so you have to have taken it.
Unless you happened to be part of the mess that happened when the grade 12 maths all had an orgy, resulting in three children: one stupidly easy course, one relatively difficult course, and while Data stayed the same on the outside, the course content seems to have been butchered into an unrecognizable mess. At my high school, at least.
While it's possible to land a co-op job after first-year Eng, it's relatively unlikely and I recommend you save the $125 or so in fees and not bother with it even if you are accepted. Some will disagree with me, but it's up to you to decide.
If your current average is 82, then you still have a little time before midterms to bring it up if you didn't already get early admission. I'd bring it up a few notches just to be safe; you can
sort of start slacking after midterm season and your acceptance is secured. Just keep it above 80 for that entrance scholarship.
Also, do
LEAP + Headstart.