I suspect that the multitude of parts in addition to the difficulty of the actual questions made Question 8 part (b) from the 1989 4 Unit Mathematics HSC paper very difficult for current and previous HSC students that use(d) these papers as practice material and of course the 1989 HSC cohort:
Imagine these questions were asked now. There would be a huge uproar, more than the crickets question from last year (which in reality wasn't that bad it was just reading).
idk about other hsc but for 2021 the worst were 14d in 3u and 16b in 4u (which i think only 5 candidates got full marks for because it was algebra hell). 16c in 4u was not so bad its just by the time you get to the end of the paper you're exhausted and can't think properly.