5. Efficient Markets (6 points) (a) (4 points) Suppose that on average we see systematically significant positive risk-adjusted returns (continued increase in prices not explained by a general increase in the market or risk) after a new product announcement by companies. Is this a violation of efficient markets hypothesis? Explain. efficiency but does not contradict (b) (2 points) Give an example of a trading strategy that contradicts semi-strong form weak form efficiency