Consider a three-factor APT model. The factors and associated risk premiums are: Pactor Change in gross national product (GNP) Change in energy prices Change in long-term interest rates Risk Premium (1) +6.6 0.7 +3.7 Calculate expected rates of return on the following stocks. The risk-free interest rate is 3.9%. a. A stock whose return is uncorrelated with all three factors. (Enter your answer as a percent rounded to 1 decimal place.) b. A stock with average exposure to each factor (.e, with bi for each). (Enter your answer as a percent rounded to 1 decimal place.) c. A pure-play energy stock with high exposure to the energy factor (b2.1) but zero exposure to the other two factors. (Enter your answer as a percent rounded to 2 decimal places.) d. An aluminum company stock with average sensitivity to changes in interest rates and GNP, but negative exposure of b-16 to the energy factor. (The aluminum company is energy Intensive and suffers when energy prices rise) (Enter your answer as a percent rounded to 2 decimal places.) % Expected rate of return Expected rate of return Expected rate of return Expected rate of return % % d *