Estimating Useful Life and Percent Used Up The property and equipment footnote from the Deere & Company Equipment and Operations segment follows. Property and Depreciation A summary of property and equipment at October 31 follows Useful Lives Land Buildings and building equipment Machinery and equipment Dies, patterns, tools, etc All other Construction in progress Property and Equipment ($ millions) (Years) 2015 2014 $114 $120 ,238 3,037 5,277 5,089 1,567 1,552 875 889 345 530 11,416 11,217 5,846 5,694 $5,570 $5,523 23 Total at cost Less accumulated depreciation Total *Weighted averages Total property and equipment additions in 2015, 2014 and 2013 were $666 million, $1,016 million and $1,158 million, and depreciation was $692 million $696 million and $637 million, respectively a. Compute the estimated useful life of Deere's depreciable assets at year-end 2015 Round answer to one decimal place x years b. Estimate the percent used up of Deere's depreciable assets at year-end 2015 Round answer to one decimal place (ex: 0.2345 23.5%) X%