Please explain clearly. Thank you so much!!

QUESTION 1 A Private Equity (PE) is holding a well-diversified portfolio that invests 70% in common share portfolio E and 30% in Risk-free Treasury bond T. The portfolio (E and T) has expected return of 7% and variance of 0.5%. If the PE is trying to rebalance its portfolio so that it invests 50% in E and 50% in T, what will be the expected return and the variance of this rebalanced portfolio based on the information given above? i. known expected return ii. unknown expected return iii. known variance iv. unknown variance O i and iii O ii and iv O i and iv O ii and