Assume the following information in Diamondback Energy's supplemental disclosures for its 2018 annual report. Estimated Quantities of Net Proved Oil and Natural Gas 2018 Oil Gas MMBO BCF Beginning of year 288 285 Revisions of previous estimates 15 3.6 Purchases of reserves in place 380 641 Sales of reserves in place 0 -1 Extensions and discoveries 176 154 Production -42 -35 End of year 817 1,049 BOE MMBOE 336 16 487 0 202 -48 992 Calculate the following reserve ratios for the year on a BOE basis, showing your formulas: a) Reserve replacement ratio including revisions. b) Reserve replacement ratio including revisions and purchases of reserves. Assume the following information in Diamondback Energy's supplemental disclosures for its 2018 annual report. Estimated Quantities of Net Proved Oil and Natural Gas 2018 Oil Gas MMBO BCF Beginning of year 288 285 Revisions of previous estimates 15 3.6 Purchases of reserves in place 380 641 Sales of reserves in place 0 -1 Extensions and discoveries 176 154 Production -42 -35 End of year 817 1,049 BOE MMBOE 336 16 487 0 202 -48 992 Calculate the following reserve ratios for the year on a BOE basis, showing your formulas: a) Reserve replacement ratio including revisions. b) Reserve replacement ratio including revisions and purchases of reserves