You have a $$12,000$ portfolio which is invested in stocks A and B$,$ and a risk$-$free asset. $$3,000$ is invested in stock A$.$ Stock A has a beta of $1\mathrm{.}76$ and stock B has a beta of $0\mathrm{.}89.$ How much needs to be invested in stock B if you want a portfolio beta of $1\mathrm{.}10?$