Depends on rear hub design. Some specials can take 9. 11 is quite common, another smallest is 14.
It's 1/8" width, but the length is determined by the size of the bike frame, and the size of the sprocket/chainwheel you're using.
The smallest sprocket is usually referred to as the "cog" and is commonly found on the rear wheel of a bicycle. It is designed to mesh with the chain and is typically the one with the fewest number of teeth among all the sprockets on the bike.
It depends on whether you are talking about the front sprocket (the one at the pedals, called a chainring) or the sprocket at the rear derailleur. The lowest gear at the front is the smallest sprocket/chainring. The lowest gear at the rear is the largest sprocket. So if you combine the smallest sprocket at the front with the largest sprocket in the rear you have the lowest gear available on your bike.
Depends. Usually there's some leeway for adaptation, but it's possible that your bike was delivered with the smallest sprocket available for that hub.
Guessing an 11T cog (sproket), maybe a custom 10T.
Chain is on the smallest sprocket on the crank and on the largest sprocket on the rear wheel
Sprocket size will b 16T & 39
13t driver goes on a 33t sprocket
Usually the sprocket is an inseparable part of the freewheel, and the size of the freewheel is determined by the hub.
The chain is size 530, and the stock gearing is 15/45, meaning that the front sprocket has 15 teeth and the rear sprocket has 45 teeth.
It uses a 47 tooth sprocket.
Any size will work. What'll work best depends on what you want it for. Higher top speed - go for a big sprocket. Quicker off the start - go for a smaller sprocket.