a$)$ Which of the four assets provides the best risk to reward ratio?

b$)$ Which combination of two assets provides the best possibilities of diversification?

c$)$ What is the beta of GLD$,$ USO, Bitcoin using S&P $500$ index as the market portfolio?

d$)$ Among GLD$,$ USO and Bitcoin three assets, please identify one asset that combine with S&P $500$ index to create a possible portfolio that provides the best risk to reward ratio. What is the return and standard deviation of the portfolio?

e$)$ Among all possible portfolios that are created with a combination of S&P $500$ index, GLD and Bitcoin, what would be the investment proportions in S&P $500$ index, GLD and Bitcoin for a portfolio that provides the best risk to reward ratio? What is the return and standard deviation of the portfolio?