Unlike a sustainable competitive advantage, a cost competitive advantage: a. does not ensure satisfactory profit margins. b. requires business firms to reduce after-purchase service options. c. involves producing goods that cannot be copied by competitors. d. is subject to continual erosion.

You wish to retire in 13 years, at which time you want to have accumulated enough money to receive an annual annuity of $23,000 for 18 years after retirement. during the period before retirement you can earn 9 percent annually, while after retirement you can earn 11 percent on your money. what annual contributions to the retirement fund will allow you to receive the $23,000 annuity? use appendix c and appendix d for an approximate answer, but calculate your final answer using the formula and financial calculator methods.