A friend of yours tells you that she found positive and statistically significant abnormal returns around such event when using the CAPM. She claims that she found positive alphas also when using the Fama-French three-factor model, the Fama-French five-factor model, and even when adding the momentum factor to all the five factors of the latter model. She thus concludes that for sure the market is not semi-strong efficient given these alphas. Is she correct? Explain why you agree or disagree with her.