On 1/1/2010, jason and hillary made an investment of x. jason invested x into a 12-year annuity-immediate with an annual payment of 5,000 each at an effective interest rate of 7%. hillary invested x in an investment fund earning an annual effective interest rate of 6%. on 1/1/2013, hillary used the accumulated value of her account to buy a 16-year annuity-due with annual payments of z earning an effective interest rate of 8%. calculate z.