A portfolio manager wants to use perpetuities with a yield to maturity of 7.5% per year and 5-year zero coupon bonds to immunize a liability with a duration of 12 years. What percent of the portfolio should he invest in the perpetuities? 1) 31.9% 2) 68.2% 3) 24.7% 4) 84.8% 5) 75.3%