Two methods are under consideration for producing the case for a portable hazardous material photoionization monitor. a plastic case will require an initial investment of $75,000 and will have an annual operating cost of $27,000 with no salvage after 2 years. an aluminum case will require an investment of $125,000 and will have annual costs of $12,000. some of the equipment can be sold for $30,000 after its 3-year life. at an interest rate of 10% per year, which case should be used on the basis of a present worth analysis?

What is the difference between total utility and marginal utility? a. marginal utility is subject to the law of diminishing marginal utility while total utility is not. b. total utility represents the consumer optimum while marginal utility gives the total utility per dollar spent on the last unit. c. total utility is the total amount of satisfaction derived from consuming a certain amount of a good while marginal utility is the additional satisfaction gained from consuming an additional unit of the good. d. marginal utility represents the consumer optimum while total utility gives the total utility per dollar spent on the last unit.