Given

$E(R_1)=0\mathrm{.}12$

$E(R_2)=0\mathrm{.}16$

$E({}_1)=0\mathrm{.}04$

$E({}_2)=0\mathrm{.}06$

Calculate the expected returns and expected standard deviations of a two$-$stock portfolio having a correlation coefficient of $0$ under the following conditions:

a$.w_1=1\mathrm{.}00$

b$.w_1=0\mathrm{.}75$

c$.w_1=0\mathrm{.}50$

d$.w_1=0\mathrm{.}25$

e$.w_1=0\mathrm{.}05$

Plot the results on a risk$-$return graph. Without calculations, draw what the curve would look like first if the correlation coefficient had been $0\mathrm{.}70$ and then if it had been $-0\mathrm{.}70.$