A rational decisionmaker Select one: a. ignores marginal changes and focuses instead on "the big picture." b. ignores the likely effects of government policies when he or she makes choices. c. takes an action only if the marginal benefit of that action exceeds the marginal cost of that action. d. takes an action only if the combined benefits of that action and previous actions exceed the combined costs of that action and previous actions.

You are the manager of a large crude-oil refinery. as part of the refining process, a certain heat exchanger (operated at high temperatures and with abrasive material flowing through it) must be replaced every year. the replacement and downtime cost in the first year is $165 comma 000. this cost is expected to increase due to inflation at a rate of 7% per year for six years (i. e. until the eoy 7), at which time this particular heat exchanger will no longer be needed. if the company's cost of capital is 15% per year, how much could you afford to spend for a higher quality heat exchanger so that these annual replacement and downtime costs could be eliminated?