What Steps Would You Follow in Order to Take Advantage

Short Answer

What steps would you follow in order to take advantage of the following arbitrage opportunity (if there is one)? Security A costs $100 and pays $110 in 2 years. Security B costs $100 and pays $109 in one year. You know that in a year with $109 you can invest in a security that pays $120 or $109 (with equal probability) the following year.