I am getting a four (4) errors and 1 Bad Box with the code below. However, the output is the way I need in the PDF. Any ideas why I am getting the errors? And if so, how I can fix it.
The error is Missing $
inserted in this code:
$y_{f}$ & $=$ & \left\{\begin{array}{rl} 1, &\mbox{ if Supplier located at site $f$ is open} \\0, &\mbox{ otherwise} \end{array} \right.\
\usepackage{mathtools}
\usepackage{amsmath}
\usepackage{amssymb}
\usepackage{tabulary}
\usepackage{booktabs}
\begin{table}[htbp]\caption{Table of Notation My Research}
\vspace{-1.5em}
\begin{center}
\begin{tabular}{r c p{10cm} }
\toprule
$R_{i}$ & $\triangleq$ & Revenue at store $i$\\
$i$ & $\triangleq$ & index value for store locations\\
${T}_{c}$ & $\triangleq$ & A very long description of this specific variable and is needed in the research and looks good when wrapped and aligned to the left.\\
$TC$ & $\triangleq$ & Total overall cost(\$)\\
\multicolumn{3}{c}{}\\
\multicolumn{3}{c}{\underline{Decision Variables}}\\
$y_{f}$ & $=$ & \left\{\begin{array}{rl} 1, &\mbox{ if Supplier located at site $f$ is open} \\
0, &\mbox{ otherwise} \end{array} \right.\\
\bottomrule
\end{tabular}
\end{center}
\label{tab:TableOfNotationForMyResearch}
\end{table}