You need a chain meant for single-speed or internally geared bikes, cut to the right length.
Guessing an 11T cog (sproket), maybe a custom 10T.
10t - 21, possibly. Or (-10t + 21)-1
89+2t = 10t+25 89-25 = 10t-2t 64 = 8t t = 8
To the rest of the cycling world what you're calling sprocket would be a chainwheel, or possibly a chainring. And what you're calling a cassette is a single-speed freewheel. On top of that I don't think there is such a thing as a 10T freewheel. 16 is pretty much the standard, there is a rare 15T that will still fit standard hubs, and you can get as low as 13 if you go to custom builds. And yes, the 44/16 is the stock configuration, and at that price range I don't think the shop will be too interested in setting you up with something else unless you pay them for it. But the only way to find out for sure is by asking them.
10t
2/(5t-4)=2 2=10t-8 10=10t t=1
ID-10T fault.
10t=6t+24 -6 -6 4t=24 4 4 1=6 t=6
No
10t
You combine like terms.
on 10t september