Suppose you have $10,000 in cash and you decide to borrow another $10,000 at a 6% interest rate to invest in the stock market. You invest the entire $20,000 in a market portfolio with a 12% expected return and a 20% volatility. The expected return of your portfolio is %. (Please write percentage as a number with one decimal place, no "%" sign. e.g. write "12.34%" as "12.3")