1. What are the chances of any us surviving outside of human civilization if all technology was stripped from us, even if we had memorized all of humanity's combined knowledge?
2. How long would it take to replicate current technology from scratch, if all the research was already done for you, and you were basically immortal?
By "from scratch" I mean skipping the creating-the-universe part, just starting without any preexisting tools other than what you may find in nature.
Maintenance is a killer. There comes a point, fairly early in technological development, where it's simply impossible for any single person to keep everything working and still have time to improve on the situation.
That's true for even the most benign of environments. Hana, unfortunately, was stuck in a rather damp jungle.
(And to preempt the possibly inevitable question, find it at https://forums.sufficientvelocity.com/threads/song-in-the-fo.... Read if you feel like; I like to think it's cute.)
Of course the daily grind there is probably food production and medical issues.