96-38. Estimating Useful Life and Percent Used Up The property and equipment section of the lululemon athletica 2018 balance sheet follows. Depreciation expense related to property and equipment was $122.4 million and $108.0 million for the years ended February 3,2019 , and January 28,2018 , respectively. Required a. Consider the level of the various PPE components. Does it seem likely that the company manufactures its own inventory? Why or why not? b. What is meant by "work in progress"? Explain how this item will be accounted for in the coming months at lululemon. c. Compute the estimated useful life of lululemon's depreciable assets. d. Compute the estimated percent used up of lululemon's depreciable assets. How do we interpret this figure