19. (0.5 point) A four-year $1,000 bond will pay $60 in interest at the end of each year. With a yield-to-maturity of 8%, its present market price is $934. Its duration is (a) 1.88 years. (b) 3.66 years. (c) 3.28 years. (d) 4.32 years. 20. (0.5 point) A pension plan will have a cash outflow in 3 years. They can invest in 2 year bonds with duration of 1.7 years and 4 year bonds with a duration of 3.5 years. To immunize the portfolio, the proportion invested in the 4 year bonds should be (a) 0.44. (b) 0.28. (c) 0.5. (d) 0.72