9. An engineering consulting firm is evaluating the two processes shown below at an interest rate of 8% per year compounded semi-annually. If an annual worth comparison is used, the annual worth of alternative M is closest to: First Cost, $ Semi-annual cost, $/6 mos. Salvage Value, $ Alt M 50,000 7,000 5,000 Alt P 82,000 3,000 8,000 4 Life, years a. -$13,575 b. -$15,785 c. -$16,975 d. -$18,625 10. A bulk materials hauler purchased a used dump truck for $40,000. The operating cost was $5,000 per month, with average revenues of $8,000 per month. After 2 years, the truck was sold for $12,000. The rate of return was closest to: a. 2% per month b. 4% per month C. 10% per month