Code: Select all
\documentclass[fleqn]{article}
\usepackage{enumitem}
\usepackage{fullpage}
\usepackage{amsmath}
\usepackage{tikz}
\usetikzlibrary{arrows}
\usetikzlibrary{intersections}
\usepackage[makeroom]{cancel}
\pagestyle{empty}
\setlength{\mathindent}{0pt}
\usepackage[version=3]{mhchem}
\usepackage{chemfig}
\setenumerate[2]{label=\alph*),leftmargin=0.5cm,font=\sffamily}
\setenumerate[1]{label=A-\arabic*.,leftmargin=-1cm,font=\sffamily}
\allowdisplaybreaks
\begin{document}
\begin{tikzpicture}[>=triangle 60]
\draw [<-] (-5,0) -- (-1,0);
\draw [<-] (5,0) -- (1,0);
\node [circle,draw,inner sep=0pt] {\begin{tikzpicture}[scale=0.4] \draw (-1,0) -- (1,0); \draw (0,1) -- (0,-1); \end{tikzpicture}};
\end{tikzpicture}
\end{document}