The annualized YTM on a single-period pure discount bond is 12% and that on a two-period pure discount bond is 10.45%. There are two bonds. One is a two-period, pure discount bond that promises a balloon payment of $1200 at maturity. The other is a bond that will pay a coupon of $100 one period hence, and a coupon of $100 plus a balloon payment of $1000 two periods hence. Compute the duration of these bonds and their possible price changes prior to maturity.