7. You have $75,000 invested in three stocks as follows: Stock Stryker Medical Disney Microsoft Investment $25,000 $25,000 $25,000 Stock's Beta 1.2 1.8 0.9 (a) What is the beta value of your portfolio? (b) You desire a portfolio beta of 1.5 and will achieve this by selling a portion of your Microsoft stock and using the proceeds from the sale to purchase additional Disney stock. What dollar amount of Microsoft stock should you sell to purchase Disney stock, to obtain a portfolio beta of 1.5