Given the quality of the work, I suspect that 2x-5x that many hours were spent on developing and revising the story (the parenthetical part). So let's call it 66 hours total.
Later:
> 8/27/2020 - RUOXI FROM TOR.COM EMAILED TO BUY THE STORY! They offered $1422.80 for exclusive digital, audio, and ebook rights for one year, non-exclusive afterward. Likely publication: early 2021. I said yes!
So, ballpark $20/hr. Some commenters have noted the low pay for this kind of work. How it's a labor of love rather than a living. And Tor apparently pays top dollar. On top of the fee, there's a profit sharing program, which starts to sound pretty good. But again, this looks to be the ceiling.
What's more interesting are the non-financial terms. The author can sell the work to others after one year. Depending on whether the author retains copyright (seems to be implied), this could be a pretty interesting way to go. I'm thinking about things like expansion into a novel, movie or other derivative works, for example. The acceptance letter doesn't quite make it clear how this works. How does it work?