ou own a portfolio invested $30$ percent in stock A$,20$ percent in stock B$,10$ percent

in stock C$,$ and $40$ percent in stock D$.$ The betas for these four stocks are $1$:$2,0$:$6,1$:$5,$

and $0$:$8,$ respectively. What is the beta of this portfolio?

$($a$)0$:$75$

$($b$)0$:$85$

$($c$)0$:$95$

$($d$)1$:$05$