How would I calculate the basic earnings per share, return on assets, and return on common shareholders' equity for both years using these financial statements?

Consolidated Statements Of Income - USD ($) $ in Millions 12 Months Ended Dec. 31, 2020 Dec 31, 2019 $ 171,760 $ 181,193 32,909 38,039 18,880 28,516 165,355 6,405 34,356 39,422 1,458 28,217 153,238 27,955 Operating Revenues Total operating revenues Cost of revenues Other cost of revenues (exclusive of depreciation and amortization shown separately below) Selling, general and administrative Asset impairments and abandonments Depreciation and amortization Total operating expenses Operating Income (Loss) Other Income (Expense) Interest expense Equity in net income (loss) of affiliates Other income (expense) net Total other income (expense) Income (Loss) Before Income Taxes Income tax expense Net Income (Loss) Less: Net Income Attributable to Noncontrolling Interest Net Income (Loss) Attributable to AT&T Less: Preferred Stock Dividends Net Income (Loss) Attributable to Common Stock Basic Earnings Per Share Attributable to Common Stock (in dollars per share) Diluted Earnings Per Share Attributable to Common Stock (in dollars per share) Service Operating Revenues Total operating revenues Equipment Operating Revenues Total operating revenues Cost of revenues Cost of goods and services sold Broadcast, programming and operations Cost of revenues Cost of goods and services sold (7,925) 95 (1,431) (9,261) (2,856) 965 (3,821) (1,355) (5,176) (193) $ (5,369) $ (0.75) $ (0.75) (8,422) 6 (1,071) (9,487) 18,468 3,493 14,975 (1,072) 13,903 (3) $ 13,900 $ 1.90 $ 1.89 $ 152,767 $ 163,499 18,993 17,694 19,706 18,653 $ 27,305 $ 31,132 Dec. 31, 2020 Dec. 31, 2019 $ 9,740 20,215 1,822 20,231 52,008 14,752 127,315 135,259 93,840 15,386 1.780 $ 12,130 22,636 1,631 18,364 54,761 12,434 130,128 146,241 97,907 20.798 24,714 3,695 24,039 22.754 551,669 23,617 525,761 3,470 49,032 6,176 1,019 3,741 63,438 153,775 11,838 45,956 6,124 1,212 3,781 68,911 151,309 Consolidated Balance Sheets - USD ($) $ in Millions Current Assets Cash and cash equivalents Accounts receivable - net of related allowance for credit loss of $1,221 and $1,235 Prepaid expenses Other current assets Total current assets Noncurrent Inventories and Theatrical Film and Television Production Costs Property, Plant and Equipment - Net Goodwill Licenses - Net Other Intangible Assets - Net Investments in and Advances to Equity Affiliates Operating Lease Right-Of-Use Assets Other Assets Total Assets Current Liabilities Debt maturing within one year Accounts payable and accrued liabilities Advanced billings and customer deposits Accrued taxes Dividends payable Total current liabilities Long-Term Debt Deferred Credits and Other Noncurrent Liabilities Deferred income taxes Postemployment benefit obligation Operating lease liabilities Other noncurrent liabilities Total deferred credits and other noncurrent liabilities Stockholders' Equity Common stock ($1 par value, 14,000,000,000 authorized at December 31, 2020 and December 31, 2019: issued 7,620,748,598 at December 31, 2020 and December 31, 2019) Additional paid-in capital Retained earnings Treasury stock (494,826,583 at December 31, 2020 and 366,193,458 at December 31, 2019, at cost) Accumulated other comprehensive income Noncontrolling interest Total stockholders' equity Total Liabilities and Stockholders' Equity Series A (48,000 issued and outstanding at December 31, 2020 and December 31, 2019) Stockholders' Equity Preferred stock ($1 par value, 10,000,000 authorized): Series B (20,000 issued and outstanding at December 31, 2020 and 0 issued and outstanding at December 31, 2019) Stockholders' Equity Preferred stock ($1 par value, 10,000,000 authorized): Series C (70,000 issued and outstanding at December 31, 2020 and O issued and outstanding at December 31, 2019) Stockholders' Equity Preferred stock ($1 par value, 10,000,000 authorized): Trademarks And Trade Names - Net Current Assets Finite-Lived Intangible Assets - Net Distribution Networks - Net Current Assets Finite-Lived Intangible Assets - Net 60,472 18.276 22,202 28,358 129,308 59,502 18.788 21,804 29,421 129,515 7,621 7,621 130,175 37,457 (17,910) 126,279 57,936 (13,085) 4,330 17,567 179,240 525,761 5,470 17,713 201,934 551,669 0 0 0 0 0 0 0 0 23,297 23,567 $ 13,793 $ 15,345