what is the simulated focal length and megapixels at 10x zoom?

I

iMore Question

I know that on the iPhone pro it has a 0.5, 1 and 2x zoom. then it can simulate a zoom up to 10 x though that digital and not as good as optical.

but I'm curious what is the simulated focal length at 10x?

secondly because obviously digital zoom degrades the quality I'm thinking maybe a 12 megapixel at 1x zoomed in 2x digitally would be equivalent quality to 6 megapixels unzoomed. maybe 4x is the same as 3 megapixels, etc. is that right and if so what is 10X on the iphone megapixel wise? 2 megapixels? thanks!