The risk free rate is $4\%.$ The risky portfolio has an expected return of $15\%$ and a return volatility of $20\%.$ Investors can create complete portfolios out of these two assets. Answer the following questions: A$.$ If an investor wants his complete portfolio to have an expected return of $12\%,$ what is his capital allocation to the risky portfolio?

B$.$ If the investor has $$1000$ to invest, how does he invest this money to achieve such a complete portfolio?