I got a 5 as well, but in my case it was less a function of calculus mastery and more a function of knowing how to program everything they asked for into a TI-8

I got a 5 as well, but in my case it was less a function of calculus mastery and more a function of knowing how to program everything they asked for into a TI-89. (I've since gone through a few calculus textbooks to actually learn everything that gizmo let me fake an understanding of.)