Yes. All hamsters will bite if they feel immediately threatened or very annoyed. Hamsters will also bite if they aren't used to human interaction. Syrian hamsters will bite each other (continually until one kills the other) and therefore can't live in the same space once they're four or so weeks old.
Well-adjusted hamsters will make spiff/squeaking noises when irritated, take this as a warning (like when a dog growls) and stop whatever you're doing to bother it. Otherwise, if the hamster is biting you without warning or reason, flick it lightly on the nose and say "NO" loudly in a deep, calm voice. (Hamsters won't learn the word "no" but the tone, along with the LIGHT flick, will train it - it's worked for me with all of my hamsters.)
If your new hamster is biting you when you touch it, be patient and remember how confusing and scared they must be about their new home. Make sure you've done your homework looking up how to care for a new hamster, there are clear steps to get it used to you and eventually it should be very loving and tame.
Yes you can
no
Yes, you can.
All Dwarf hamster are short-haired. The Russian Dwarf, Winter White, Chinese Dwarf, Roborovski's dwarf, etc. The long-haired hamsters are Syrians.
No more than short haired. It depends on the individual.
A long haired hamster, also known as a syrian hamster, can grow up to 5-6 inches. Even though they have longer and messier coats types than a short haired hamster, a long haired hamster does not grow bigger in size than a short haired. Long haired hamsters reach their full size a within a year after birth.
you will probably get a mix
A wire cage with a plastic bottom.
If you have a short haired hamster like a Syrian then it cleans itself. If your hamster is long haired then you have to brush it depending on the length and thickness of its hair. Never bathe your hamster, they hate water and lick themselves to keep clean anyway.
A hamster can remember up to 2 or 3 months if you did something bad to it, even if you didnt mean to.
If you have a short haired hamster you wouldn't have to deal with knots in the hair, a long haired hamster has long hair that you would have to brush everyday. I have a hamster with extremely long hair and i brush everyday. That what keeps knots out of the hair. It also makes it soft. DO NOT CUT ITS HAIR, unless it is used to your hand and will stay very still. If you have a short haired hamster you don't have to brush it as much. Use a soft tipped toothbrush when brushing the fur.
By 'Teddy bear' do you mean Long-haired Syrian? And by 'black bear' do you mean black Short-Haired Syrian? Then yes. They are both Syrian.