please help with the ones i got wrong

Balance sheets and income statements for Costco Wholesale Corporation follow. Costco Wholesale Corporation Consolidated Balance Sheets (\$ millions, except par value and share data) September 2, 2018 September 3, 2017 Current assets (a) Compute net operating profit after tax (NOPAT) for 2018. Assume that the combined federal and state statutory tax rate is 22\%. (b) Compute net operating assets (NOA) for 2018 and 2017 . (c) Compute Costcos RNOA, net operating profit margin (NOPM) and net operating asset turnover (NOAT) for 2018. (d) Compute net nonoperating obligations (NNO) for 2018 and 2017. Confirm the relation: NOA = NNO + Total equity, (e) Compute return on equity (ROE) for 2018. (f) Infer the nonoperating return component of ROE for 2018