Jack, Oliver and Henry find themselves in an argument about expected stock returns. According to the Jack, because securities A and B traded on the U.S. stock market have the same betas, so he thinks their expected returns must be the same. However, Oliver disagrees by pointing out that the returns of security A have a higher standard deviation than those of security B. Henry wants to side with Jack but adds that Oliver's claim only makes sense if beta is positive. Discuss the merits and lack of each person's claim. H