0.62x0.152 + 0.42x0.052+ 2 ( 0.6 x 0.15 x 0.4 x 0.05)( -0.05 )
(0.6^2×0.15^2+0.4^2×0.05^2+2×0.4×0.6×0.15×0.05×−0.5)^0.5=0.0818
96. 某投資人,其資金60%投資股票,預期報酬率為20%,其40%投資債券,預..-阿摩線上測驗