A firm has issued 9% debentures and zero coupon bonds, both of them will mature July 19, 2015. Assume that interest is paid and compounded annually. Both debentures and zero coupon bonds have face values of $100 and $1,000 respectively. If an investor purchases the debentures for $110 on July 19, 2010 and pays $115 for the zero coupon bond on July 19, 2000:

1. Determine the debentures' yield to maturity
2. Compute the zero coupon bond's yield to maturity