The standard deviation of a portfolio that has $40\%$ of its value invested in a risk$-$free asset and $60\%$ of its value invested in a risky asset with a standard deviation of $30\%$ is

Question $15$Answer

a$.$

$18\%.$

b$.$

$24\%.$

c$.$

$20\%.$

d$.$

$21\%.$

e$.$

$14\%.$