A mutual fund manager has a $20 million portfolio with a beta of 1.7. The risk-free rate is 4.5%, and the market risk premium is 7%. The manager expects to receive an additional $5 million, which she plans to invest in a number of stocks. After investing the additional funds, she wants the fund's required return to be 15%. What should be the average beta of the new stocks added to the portfolio?

a) Find the weights of the new and old portions of the total new portfolio

b) Find beta of the new additional part of the portfolio