Assume Urgent Care paid $42,000 for X-ray equipment four years ago. The equipment was expected to have a useful life of 10 years from the date of acquisition with annual operating costs of $25,000. Technological advances have made the machine purchased four years ago obsolete with a zero salvage value. An improved X-ray device incorporating the new technology is available at an initial cost of $50,000 and annual operating costs of $15,000. The new machine is expected to last only six year