Early in the current year, Amazon Co. purchased the Rio Silver Mine at a cost of $30,000,000. The mine was estimated to contain 400,000 tons of ore and to have a residual value of $7,500,000 after mining operations are completed. During the year, 115,000 tons of ore were removed from the mine. At year-end, the book value of the mine is:

Exercise 18-15 sheffield appliance center is an experienced home appliance dealer. sheffield appliance center also offers a number of services for the home appliances that it sells. assume that sheffield appliance center sells ovens on a standalone basis. sheffield appliance center also sells installation services and maintenance services for ovens. however, sheffield appliance center does not offer installation or maintenance services to customers who buy ovens from other vendors. pricing for ovens is as follows. oven only $790 oven with installation service 850 oven with maintenance services 970 oven with installation and maintenance services 990 in each instance in which maintenance services are provided, the maintenance service is separately priced within the arrangement at $180. additionally, the incremental amount charged by sheffield appliance center for installation approximates the amount charged by independent third parties. ovens are sold subject to a general right of return. if a customer purchases an oven with installation and/or maintenance services, in the event sheffield appliance center does not complete the service satisfactorily, the customer is only entitled to a refund of the portion of the fee that exceeds $790. assume that a customer purchases an oven with both installation and maintenance services for $990. (b) indicate the amount of revenue that should be allocated to the oven, the installation, and to the maintenance contract.

Specialization—the division of labor—enhances productivity and efficiency by a) allowing workers to take advantage of existing differences in their abilities and skills. b) avoiding the time loss involved in shifting from one production task to another. c) allowing workers to develop skills by working on one, or a limited number, of tasks. d)all of the means identified in the other answers.

Classify each of the following items as a public good, a private good, a natural monopoly good, or a common resource.(a) measles vaccinations (b) tuna in the pacific ocean (c) airline service in the united states (d) local storm-water system