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. Total property and equipment additions in 2015, 2014 and 2013 were $666 million, $1,016 million and $1,158 million, and depreciation was $692 mallion, $696 million and $637 milihion, respectively a. Compute the average useful hife of Deere's depreciable assets at year-end 2015. Round answer to one decimal place. years b. Estimate the percent used up of Deeres depreciable assets at year-end 2015. Round answer to one decimal place (exc 0.2345=23.5%)