answer all please

5. Is it possible to build a risk-free portfolio using risky assets? If yes, how? If no, why not? 6. What is worst portfolio you can make? How bad is it? 7. If an investor chooses to hold only a single stock (doesn't diversify), would the investor be compensated for the extra risk they bear? 8. How would a fall in inflation or a fall in risk aversion affect the security market line