A hospital purchased a used CT scanner for $450,000 and placed the equipment in service in January of Year 1. Per industry guidelines, the CT scanner has an estimated useful life of 5 years (60 months) and is capitalized and depreciated on a straight-line basis (i.e., equal amounts over 60 months). (a) What is the equipment's net book value after 18 months? (b) If after 55 months the asset is sold for $100,000, how much profit is realized by the hospital