Assume that you manage a risky portfolio with an expected rate of return of $12\%$ and a standard deviation of $28\%.$ The T$-$bill rate is $4\%$

A client prefers to invest in your portfolio a proportion $($y$)$ that maximizes the expected return on the overall portfolio subject to the constraint that the overall portfolio's standard deviation will not exceed $20\%.$

Required:

a$.$ What is the investment proportion, y$?($Do not round intermediate calculations. Round your answer to $2$ decimal places.$)$

b$.$ What is the expected rate of return on the overall portfolio? $($Do not round intermediate calculations. Round your answer to $2$ decimal places.$)$