Hello,

I do not think there is a 'simple' answer to your question.

If you check the internet there seems to be a whole lot of disagreement between teachers

and the like.

I accidently started reading about the Euler characteristic to help provide you with an answer

and that led me to being more confused than I thought possible when it came to defining

the characteristics of a sphere.

I suggest that your child would be unlikely to receive a question in an exam involving faces on spheres/cylinders as there is too much indecision on the matter.

However, if your daughter/son is asked a question about faces/vertices/edges involving the sphere - tell them to write - Euler said it's 2!

http://en.wikipedia.org/wiki/Euler_characteristicSorry this is not more helpful!