Portfilio 1
Security	Amount Invested	Expected Return	Beta
Security A	$4000	9%	.80
Security B	$5000	12%	1.15
Security C	$12000	14%	.95
Security D	$8000	15%	1.23
Portfolio 2
Security A	$3000	16%	1.22
Security B	$11000	13%	1.54
Security C	$9000	8%	.87
Security D	$6000	11%	.81
Portfolio 3
Security A	$15000	10%	1.72
Security B	$12000	9%	.81
Security C	$3000	12%	.72
Security D	$2000	15%	1.54

If the risk-free rate is 5.5 percent, which of these portfolios has the highest reward-to-risk ratio? Show your work.