Tomás y yo leemos unos libros. This is the right response becuase, the common action that people write; when it comes to books, is reading(leer). Also, you're talking in a plural form, becuase you are naming more than one person. That is becuase, it is leemos and not leer. To sum it up, the correct answer is leemos.
I believe it should be “notebook”
Vosotros is informal and Ustedes is formal
This isn’t an equation— equations require an equal sign and a variable of some sort on the other side of that said equal sign. Sorry.
