About risk and return. 1. Usually there is a (positive or negative) relation between risk and return? 2. Given two investment opportunities A and B. Both have same returns, rational investors generally prefer the one with (high or low) risks? 3. There are different types of risks. For example, reinvestment risk: it happens when investment horizon is longer than security maturity. At the end of maturity, investors get all investment back and have to re-invest at an uncertain interest rate. Please answer with a different one and explain its meaning. Do not use reinvestment risk again as your