Having received several exhausting answers to my recent question about the expansion properties of a certain graph, I now wonder whether anything is known on the following graphs of a similar nature:

1. The graph on ${\rm GF}(p)$ with $z$ adjacent to $-z$ and also to $gz$, where $g$ is a fixed primitive root mod $p$.

2. The graph on ${\rm GF}(2^n)$ with $z$ adjacent to $z+e$ and also to $gz$, where $e$ is a fixed non-zero element, and $g$ is a generating element of ${\rm GF}(2^n)$.

3. The graph on $({\mathbb Z}/2^n{\mathbb Z})^\times$ (odd residue classes mod $2^n$) with $z$ adjacent to $z^{-1}$ and also to $z+2$.

Are these (families of) graphs known to be good expanders? Can one investigate them using Selberg's 3/16-theorem or other "standard" tools used to study the graph my original question concerned with?

Having received several exhausting answers to my recent question about the expansion properties of a certain graph, I now wonder whether anything is known on the following graphs of a similar nature:

1. The graph on ${\rm GF}(p)$ with $z$ adjacent to $-z$ and also to $gz$, where $g$ is a fixed primitive root mod $p$.

2. The graph on ${\rm GF}(2^n)$ with $z$ adjacent to $z+e$ and also to $gz$, where $e$ is a fixed non-zero element, and $g$ is a generating element of ${\rm GF}(2^n)$.

3. The graph on $({\mathbb Z}/2^n{\mathbb Z})^\times$ (odd residue classes mod $2^n$) with $z$ adjacent to $z^{-1}$ and also to $z+2$.

Are these (families of) graphs known to be good expanders? Can one investigate them using Selberg's 3/16-theorem or other "standard" tools used to study the graph my original question concerned with?