Should have updated this thread, but I've figured it out. Solved it and all! I'll post the answer later tomorrow as I'm about to head to bed for my exam!
EDIT: I just scanned my working pretty quick and snipped it. will post here.
I know we need to use F = pgA(h bar), as that's what I'm given in notes and whatnot, but I can't for the life of me get this simple one done.
Any help would be GREATLY appreciated as I have an exam coming up on this.