Mary O'Leary's company ships fine wool garments from County Cork, Ireland. Five years ago she purchased some new automated packing equipment having a first cost of $125,000. The annual costs for operating, maintenance, and insurance, as well as market value data for each year of the equipment's 10-year useful life are as follows.

Year n	Operating	Maintenance	Insurance	Market Value in Year n
1	16000	5000	17000	80000
2	20000	10000	16000	78000
3	24000	15000	15000	76000
4	28000	20000	14000	74000
5	32000	25000	12000	72000
6	36000	30000	11000	70000
7	40000	35000	10000	68000
8	44000	40000	10000	66000
9	48000	45000	10000	64000
10	52000	50000	10000	61000

Now Mary is looking at the remaining 5 years of her investment in this equipment. What is the marginal cost for each of the remaining 5 years? When, if at all, should Mary replace this packing equipment with a new asset that has a minimum EUAC of $110,000?