In yahoo answers can we use "****" sign or is it a community guidelines violation in yahoo answers, and what is solicitation and examples ?

If you are referring to the percentage sign then no you can nor use it. You must spell out the word percentage. As for solicitation, it has not to do with math so I don't see where you are coming from.

As for solicitation, its definition is. to ask someone for money, information, or help: 2. to offer sex for money, usually in a public place 3. to ask for something in a persuasive way

Solicitation is when you Advertise something so if your Linking to your Blog to get Viewers to go to it thats one Example of Solicitation

Or if you have a Go Fund me page and you Post asking people to Donate to it thats a another Example of It

Yes, the asterisk can be used (it's commonly used as the multiplication symbol instead of 'x'). The % sign cannot be used in a question due to the coding of the site reading it as meaning something else- so spell out percent or use decimal form.

Solicitation would be trying too encourage others to visit a specific website or make a purchase, especially that would benefit you or someone/business associated with you.

I'm not sure what sign you are talking about.

In Y!A, "sollicitation" is defined as asking anything that isn't an answer. It includes things like

" please send me money" and "go like this video on youtube"

He has many rules