a$.$ In order to create a complete portfolio to diversify riskness and balance risk tolerance, what are the ideal steps$/$ process that a investor should consider? Please briefly explain the investment process and the decision points at each stage. $(6$ points$)$

b$.$ How do you understand the relationship between investment theory and investment practice? Or$,$ in reality, what difficulties will investors face to implement those theory? This is an open$-$end questions, you can think about the following aspect, such as Information asymmetry, market efficiency, investor sentiment$,$ etc. $(4$ points$)$