The Torch's have a required return of 5.9%, so it appears that all of the portfolios will meet the return requirement. In terms of risk, the Torch's have said that they do not want the value of their portfolio to decline more than 10% in a single year. Since we have the Sharpe ratio, return of each portfolio, and the T-bill rate, we can calculate the standard deviation for each portfolio and calculate the Safety-first ratio to see if any of the portfolios can be eliminated.
Standard deviation of Allocation 1 = (10.0 - 3.0) / 0.42 = 16.67%
Standard deviation of Allocation 2 = (7.7 - 3.0) / 0.52 = 9.04%
Standard deviation of Allocation 3 = (6.78 - 3.0) / 0.62 = 6.10%
The safety first ratio can be calculated as the expected portfolio return minus 2 standard deviations.
Safety first of Allocation 1 = 10.0% - 2(16.67%) = -23.34%
Safety first of Allocation 2 = 7.7% - 2(9.04%) = -10.38%
Safety first of Allocation 3 = 6.78% - 2(6.10%) = -5.42%
Allocation 3 is the only allocation that meets the Torch's goal of not losing more than 10% in a given year.