Stock A and B have the hollowing historical returns:La$2016(18\mathrm{.}00\%)(14\mathrm{.}50\%)201733\mathrm{.}0021\mathrm{.}80201815\mathrm{.}0030\mathrm{.}502019(0\mathrm{.}50)(7\mathrm{.}60)202027\mathrm{.}0026\mathrm{.}30$a$.$ Find the average rate of return for each stock.b$.$ Find the realized rate return for a $50-50$ portfolio for each year and average realized rate of return.c$.$ Find the standard deviation of each stock and the portfolio.d$.$ Find the CV of each stock and portfolio.e$.$ Which one would you invest in: only stock A$,$ only stock B or $50-50$ portfolio? Explain.