You are managing a portfolio of $1.0 million. Your target duration is 19 years, and you can choose from two bonds: a zero-coupon bond with maturity five years and a perpetuity, each currently yielding 2%. Required: a. How much of ( ( ) the zero-coupon bond and (i) the perpetuity will you hold in your portfolio? (Do not round intermediate calculations. Round your answers to 2 decimal places.) b. How will these fractions change next year if target duration is now eighteen years? (Do not round intermediate calculations. Round your answers to 2 decimal places.)