Suppose Intel's stock has an expected return of 26.0% and a volatility of 50.0%, while Coca-Cola's has an expected return of 6.0% and volatility of 25.0%.

If these two stocks were perfectly negatively correlated (i.e., their correlation coefficient is negative 11),

a. Calculate the portfolio weights that remove all risk.

b. If there are no arbitrage opportunities, what is the risk-free rate of interest in this economy?