Centered table with left aligned text

Question

I am making a centered table but want the headings in the far left column to be left-aligned instead of centred.

Preamble:

\documentclass[11pt]{article}
\usepackage{indentfirst}
\usepackage[top=1in, bottom=1in, left=1in, right=1in]{geometry}
\usepackage{amsfonts}
\usepackage{amsmath}
\usepackage{graphicx}
\usepackage{caption}
\usepackage{subcaption}

Table code:
\begin{table}[ht]
\caption{Regression standard errors} % title of Table
\centering % used for centering table
\begin{tabular}{c c c c c} % centered columns (4 columns)
\hline\hline %inserts double horizontal lines
Confidence Interval & N=10 & N=30  & N=100 & N=500 \\ [0.5ex] % inserts table 
%heading
\hline % inserts single horizontal line
Asymptotic & \% & \% & \% & \% \\
Efron & \% & \% & \% & \% \\
Hall & \% & \% & \% & \%   \\
Percentile-t & \% & \% & \% & \% \\
Symmetric percentile-t & \% & \% & \% & \% \\ [1ex] % [1ex] adds vertical space
\hline %inserts single line
\end{tabular}
\label{table:nonlin} % is used to refer this table in the text
\end{table}

Answer 1

Use l (ell) column specifier if you want all cells in the left column to be left aligned:

\begin{tabular}{l c c c c} % centered columns (4 columns) 

If only one cell entry needs to be left aligned, use \multicolumn

\begin{tabular}{c c c c c} % centered columns (4 columns)
.
.
.

\multicolumn{1}{l}{Confidence Interval}