Comma problem after ''and''

First Question:

At times I face sentences of sort like:

I ate rice, kebab, and salad.

I ate rice, kebab, and, salad.

Sometimes comma is used after and but other times it is just omitted. Which sentence is correct in your opinion? If both above sentences have been correctly punctuated then is there still any choice for a third one?

Second Question:

Is this sentence correct?

If both above sentences have been correctly punctuated then is there still any choice for a third one?

Jackson6612 wrote:

Second Question: Is this sentence correct? If both above sentences have been correctly punctuated then is there still any choice for a third one?

Here are my two cents:

If both of the above are correct, are there any possible various versions?