Consider a single factor APT. Portfolio A has a beta of 2.0 and an expected return of 19%. Portfolio B has a beta of 1.3 and an expected return of 8%. The risk-free rate of return is 3%. You can create a portfolio D which invests ____% in portfolio A and the rest in the risk-free asset so that it has the same beta as portfolio B, and compare the returns to portfolio D and portfolio B to decide the direction of arbitrage trading.