Which of the following statements regarding investment risk is correct? 1. Beta is a measure of systematic, non-diversifiable risk 2. Rational investors will form portfolios and eliminate systematic risk. 3. Rationat investors will form portfolios and eliminate unsystematic ristic. 4. Systematic risk is the relevant risk for a well-diversified portfolio. 5. Standard devintion captures all the risk inherent in an individuat security. 2.3 , and 4 . zand 5 1,2 and 4. 1. 3 in and 5