In the following table, how can I make the title of the second (Income Mean) and the sixth column (Social Weights) to be at the center of the cell?
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\usepackage{threeparttable}% Alternative for Notes below table
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\title{Is Resource Constraint Satisfied Along The Equilibrium Path?}
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% Table generated by Excel2LaTeX from sheet 'Sheet1'
\begin{table}[htbp]
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\begin{tabular}{llcccccccccc}
\toprule
\multicolumn{12}{c}{\textbf{ARP- Average rate progression preserving- No Behavioral Effect}} \\
\midrule
\multicolumn{1}{p{5.125em}}{Income Brackets} & \multicolumn{1}{p{11.94em}}{Income Mean} & \multicolumn{1}{p{5.19em}}{Marginal Tax Rate} & \multicolumn{1}{p{5.19em}}{Taxable Income Elasticities} & \multicolumn{1}{p{5.19em}}{Income Elasticities} & \multicolumn{1}{p{4.125em}}{Social Weights} & \multicolumn{1}{p{5.19em}}{New Marginal Tax Rate} & \multicolumn{1}{p{4.375em}}{Tax Liability} & \multicolumn{1}{p{6.375em}}{Change in Tax Revenue} & \multicolumn{1}{p{5.19em}}{Transfer} & \multicolumn{1}{p{6.19em}}{Change in Diposable Income} & \multicolumn{1}{p{5.19em}}{Abatement Costs} \\
\midrule
0-10000 & \multicolumn{1}{c}{4800} & 0.10 & 0.00 & 0.10 & 0.84 & 0.11 & 528 & 48.00 & 428.04 & 380.04 & 985.02 \\
10000-32000 & \multicolumn{1}{c}{20050} & 0.15 & 0.00 & 0.10 & 1.03 & 0.16 & 2708 & 200.50 & 438.18 & 237.68 & 596.98 \\
32000-75000 & \multicolumn{1}{c}{46200} & 0.27 & 0.00 & 0.10 & 1.01 & 0.28 & 8596 & 462.00 & 572.07 & 110.07 & 261.33 \\
75000+ & \multicolumn{1}{c}{138100} & 0.45 & 0.00 & 0.10 & 0.13 & 0.46 & 45686 & 1381.00 & 653.21 & -727.79 & -1376.25 \\
Total & & & & & & & & 2091.50 & 2091.50 & 0.00 & 467.07 \\
& & & \multicolumn{1}{l}{\textbf{MCPF:}} & \textbf{0.53} & \multicolumn{1}{l}{\textbf{Environmental MCPF:}} & \textbf{0.82} & \multicolumn{1}{l}{\textbf{Difference:}} & \textbf{0.28} & & & \\
\cmidrule{2-10} & \textbf{Abatement cost per pound} & 0.00 & 0.10 & 0.25 & 0.50 & 1.00 & 1.50 & 2.00 & 2.50 & & \\
& \textbf{Total change in tax revenue} & 2091.50 & 2091.50 & 2091.50 & 2091.50 & 2091.50 & 2091.50 & 2091.50 & 2091.50 & & \\
& \textbf{Toal abatement cost} & 0.00 & 99.49 & 248.73 & 497.46 & 994.92 & 1492.39 & 1989.85 & 2487.31 & & \\
& \textbf{Abatement cost/Tax revenue} & 0.00 & 0.05 & 0.12 & 0.24 & 0.48 & 0.71 & 0.95 & 1.19 & & \\
& \textbf{Environmental MCPF} & 0.53 & 0.59 & 0.68 & 0.83 & 1.13 & 1.43 & 1.73 & 2.03 & & \\
\midrule
\multicolumn{12}{c}{\textbf{ARP- Average rate progression preserving}} \\
\midrule
0-10000 & \multicolumn{1}{c}{4800} & 0.10 & 0.40 & 0.10 & 0.84 & 0.11 & 525.65 & 45.65 & 301.34 & 234.36 & 607.43 \\
10000-32000 & \multicolumn{1}{c}{20050} & 0.15 & 0.28 & 0.10 & 1.03 & 0.16 & 2697.28 & 189.78 & 308.49 & 51.71 & 129.89 \\
32000-75000 & \multicolumn{1}{c}{46200} & 0.27 & 0.27 & 0.10 & 1.01 & 0.28 & 8549.04 & 415.04 & 402.74 & -180.01 & -427.38 \\
75000+ & \multicolumn{1}{c}{138100} & 0.45 & 0.48 & 0.10 & 0.13 & 0.46 & 45126.97 & 821.97 & 459.87 & -1577.38 & -2982.84 \\
Total & & & & & & & & 1472.45 & 1472.45 & -1471.32 & -2672.90 \\
& & & \multicolumn{1}{l}{\textbf{MCPF:}} & \textbf{0.77} & \multicolumn{1}{l}{\textbf{Environmental MCPF:}} & \textbf{-0.92} & \multicolumn{1}{l}{\textbf{Difference:}} & \textbf{-1.70} & & & \\
\cmidrule{2-10} & \textbf{Abatement cost per pound} & 0.00 & 0.10 & 0.25 & 0.50 & 1.00 & 1.50 & 2.00 & 2.50 & & \\
& \textbf{Total change in tax revenue} & 1472.45 & 1472.45 & 1472.45 & 1472.45 & 1472.45 & 1472.45 & 1472.45 & 1472.45 & & \\
& \textbf{Toal abatement cost} & 0.00 & -549.53 & -1373.82 & -2747.63 & -5495.26 & -8242.90 & -10990.53 & -13738.16 & & \\
& \textbf{Abatement cost/Tax revenue} & 0.00 & -0.37 & -0.93 & -1.87 & -3.73 & -5.60 & -7.46 & -9.33 & & \\
& \textbf{Environmental MCPF} & 0.77 & 0.39 & -0.18 & -1.12 & -3.02 & -4.92 & -6.82 & -8.71 & & \\
\midrule
\multicolumn{12}{c}{\textbf{LIP- Liability progression preserving}} \\
\midrule
0-10000 & \multicolumn{1}{c}{4800} & 0.10 & 0.40 & 0.10 & 0.84 & 0.10 & 484.58 & 4.58 & 59.68 & 52.96 & 137.28 \\
10000-32000 & \multicolumn{1}{c}{20050} & 0.15 & 0.28 & 0.10 & 1.03 & 0.15 & 2531.05 & 23.55 & 61.10 & 27.50 & 69.06 \\
32000-75000 & \multicolumn{1}{c}{46200} & 0.27 & 0.27 & 0.10 & 1.01 & 0.27 & 8202.99 & 68.99 & 79.77 & -34.51 & -81.93 \\
75000+ & \multicolumn{1}{c}{138100} & 0.45 & 0.48 & 0.10 & 0.13 & 0.45 & 44499.49 & 194.49 & 91.08 & -650.29 & -1229.71 \\
Total & & & & & & & & 291.62 & 291.62 & -604.34 & -1105.30 \\
& & & \multicolumn{1}{l}{\textbf{MCPF:}} & \textbf{0.99} & \multicolumn{1}{l}{\textbf{Environmental MCPF:}} & \textbf{-4.09} & \multicolumn{1}{l}{\textbf{Difference:}} & \textbf{-5.08} & & & \\
\cmidrule{2-10} & \textbf{Abatement cost per pound} & 0.00 & 0.10 & 0.25 & 0.50 & 1.00 & 1.50 & 2.00 & 2.50 & & \\
& \textbf{Total change in tax revenue} & 291.62 & 291.62 & 291.62 & 291.62 & 291.62 & 291.62 & 291.62 & 291.62 & & \\
& \textbf{Toal abatement cost} & 0.00 & -227.30 & -568.24 & -1136.48 & -2272.96 & -3409.44 & -4545.92 & -5682.39 & & \\
& \textbf{Abatement cost/Tax revenue} & 0.00 & -0.78 & -1.95 & -3.90 & -7.79 & -11.69 & -15.59 & -19.49 & & \\
& \textbf{Environmental MCPF} & 0.99 & -0.06 & -1.62 & -4.24 & -9.46 & -14.68 & -19.91 & -25.13 & & \\
\bottomrule
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\label{tab:addlabel}%
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\centering
help? E. g.\multicolumn{1}{p{4.125em}}{\centering Social Weights}
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