10.39.3 Can you answer these questions?

10.39.3.1 TeXMaker compilation error

https://tex.stackexchange.com/landing/r/digest?cta=question&id=719551

I am trying to compile a document (using TexMaker) that was initially setup by another person and I keep getting the following error: 
Process started  This is BibTeX, Version 0.99d (TeX Live 2023) The ... 
[bibtex] [texmaker]
 

asked by Janice Carter https://tex.stackexchange.com/landing/r/digest?cta=user&id=303994 Score of 1

10.39.3.2 Two columns with changes to a single column

https://tex.stackexchange.com/landing/r/digest?cta=question&id=719520

I would like to have a document that uses two columns.  But in some instances, e.g. for diagrams, and particular part involving equations, I turn to single column.  Then continue with two columns.  ... 
[two-column]
 

asked by Franklin https://tex.stackexchange.com/landing/r/digest?cta=user&id=321196 Score of 1

10.39.3.3 Shade between x-values given in an external file - pgfplots

https://tex.stackexchange.com/landing/r/digest?cta=question&id=719801

I'd like to achieve the following plot: 
\documentclass[a4paper]{article} 
\usepackage{pgfplots} 
\pgfplotsset{compat=1.17} 
\begin{document} 
\begin{filecontents}{data.txt} 
start,end 
1,23 
51,69 
106,165 
... 
[pgfplots] [pgfplotstable]
 

asked by cedi123 https://tex.stackexchange.com/landing/r/digest?cta=user&id=273679 Score of 1