3.16.3 Can you answer these questions?

Can you answer these?

3.16.3.1 nesting documentclasses

https://tex.stackexchange.com/questions/366507/nesting-documentclasses

I'm creating (beamer) slides explaining the basics of using LaTeX. For this purpose I would like to illustrate how some source code 
\documentclass{article} 
\title{My first paper} 
\begin{document} 
...
 

- asked by Henning Koehler 1vote

3.16.3.2 Underscore in Pathway

https://tex.stackexchange.com/questions/366738/underscore-in-pathway

I'm beginning with Latex and I want to add some JavaCode in it. My source code is in "D:\Eclipse_Projects\Algorithimique\src\s09" but I think the underscore is making trouble. 
I use the following code  ...
                                                                                  

                                                                                  
 

- asked by Warok 1vote

3.16.3.3 How to set the our own font to equation?

https://tex.stackexchange.com/questions/366926/how-to-set-the-our-own-font-to-equation

Here is the code I used: 
\documentclass[10pt]{extarticle} 
\usepackage{color} 
\usepackage{amsmath} 
\usepackage{amsfonts} 
\usepackage{amssymb} 
\usepackage{hyphenat} 
\usepackage{mathtools} 
...
 

- asked by jagannathan jothi 1vote

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