The figure below exhibits the historical trade-off between risk and return in various portfolios. ACCORDING TO THIS FIGURE, which of the following statements is TRUE? 25% Small Stocks 20% Mid-Cap Stocks 15% S&P 500 Historical Average Return 10% Corporate Bonds World Portfolio 8.5% historical excess return of S&P 500 over TBills Treasury Bills 0% 0% 5% 45% 50% 10% 15% 20% 25% 30% 35% 40% Historical Volatility (standard deviation) The portfolio of small stocks has higher total risk than that of mid-cap stocks The world portfolio has higher total risk than the S&P 500 portfolio The portfolio of corporate bonds has higher idiosyncratic risk than that of Treasury bills! The S&P 500 portfolio has higher systematic risk than the portfolio of Treasury bills