7.20.3 Can you answer these questions?

7.20.3.1 Inference justification labels for sequent calculus proofs in bussproofs

https://tex.stackexchange.com/landing/r/digest?cta=question&id=588701

I'm working through Computability and Logic and need to construct proofs the same way they do in the book. However, I can't find anything about how to give inference justifications that are on the ... 
[bussproofs]
 

asked by nolanwhitaker https://tex.stackexchange.com/landing/r/digest?cta=user&id=238236 1 vote

7.20.3.2 Force Multicolumn headers to obey Page Margins like non multicolumn tables

https://tex.stackexchange.com/landing/r/digest?cta=question&id=588901

Issue: 
I want to generate a table like ( table #2 ) that has two child columns for one parent column, but I also want this table to obey page margins and not stick out from the rest of them. (the ... 
[multicolumn]
 

asked by tblev https://tex.stackexchange.com/landing/r/digest?cta=user&id=215404 1 vote

7.20.3.3 Text in my table is not well formatted

https://tex.stackexchange.com/landing/r/digest?cta=question&id=588911

\documentclass[12pt, oneside, a4paper,titlepage]{book} 
\usepackage[italian]{babel} 
\usepackage{geometry}\usepackage{amsthm} 
\geometry{a4paper, top = 2cm, right = 2cm, left = 2cm, bottom = 2cm} 
\... 
[xltabular]
 

asked by Hello https://tex.stackexchange.com/landing/r/digest?cta=user&id=238357 1 vote