The Fama-French three-factor (FF3) model of stock returns relates stock return to market risk premium, excess returns of small-cap companies over large-cap companies, and excess returns of high book-to-price ratio over and above low book-to-price ratio.

a) In so far as small cap companies tend to exhibit higher likelihood of faster growth than large cap stocks, while high book-to-price ratio companies tend to be capital rich lower growth stocks than low book-to-price ratio companies, what problem do you see imbedded within the FF3 model? Explain your reasoning.

b) As we move from FF3 to Fama-French five-factor (FF5) model, do you expect the above problem to be exacerbated or ameliorated by the inclusion of the two additional factors into the model? Explain your reasoning.