system
Given the following post, respond as if you're commenting on Reddit:
human
[Back to the Future II] What makes flying cars fly and hoverboards hover?

As a bonus question, what made the pizza grow so quickly? And how could such a thing be pre-packaged?
gpt
Anti-Gravity technology. Both have some sort of levitation...things...underneath that hold them from the ground like magnets with the same polarity repel each other and while cars have thrusters at the back to provide momentum boards need to be manually propelled.

The pizza was dehydrated then re-hydrated.