9.80.3 Can you answer these questions?

9.80.3.1 Kinked Demand Curve

https://tex.stackexchange.com/landing/r/digest?cta=question&id=702299

\documentclass{article} 
\usepackage{pgfplots} 
\pgfplotsset{compat=1.18} 
\begin{document} 
\begin{tikzpicture} 
\begin{axis}[ 
axis lines = left, 
xlabel = $Q$, 
ylabel = {$P$}, 
xmin=0, ... 
[tikz-pgf] [citing] [positioning] [titles] [transparency]
 

asked by Muhammad Raafiansyah https://tex.stackexchange.com/landing/r/digest?cta=user&id=308724 Score of 1

9.80.3.2 textcolor and displaystyle

https://tex.stackexchange.com/landing/r/digest?cta=question&id=702297

I need to color a portion of a displayed equation, but when I do that the equation gets turned into \textstyle instead of \displaystyle.  Here is a minimal working example: 
\documentclass{amsart} 
\... 
[equations] [color] [displaystyle]
 

asked by underflow https://tex.stackexchange.com/landing/r/digest?cta=user&id=183182 Score of 1

9.80.3.3 Change bibliography starting number.... doesn't work

https://tex.stackexchange.com/landing/r/digest?cta=question&id=702161

\bibliography{} starting from any number 
I'm following this,but it doesn't work for some package 
Can anyone help how can do it with the package? 
[bibliographies] [bibtex] [numbering] [counters]
 

asked by Gobi https://tex.stackexchange.com/landing/r/digest?cta=user&id=47370 Score of 1