Breeden (1979) specified a CCAPM that collapses the multi-beta Merton

(1973) ICAPM into a single-beta equation. Write this model and define its variables and parameters. Why did he believe that the CCAPM was a better model than the CAPM from a theoretical perspective as well as in terms of empirical testing? Later work by Breeden et al. (1989) conducted empirical tests of the CCAPM. What did they find?