Explanation of でもあります？


[![enter image description
here](https://i.stack.imgur.com/fR2pR.jpg)](https://i.stack.imgur.com/fR2pR.jpg)

I saw this in my Genki I book and I don’t quite understand how to use でもあります.
Also, how would I say this informally? パットはアメリカ人でもある？

