Read the "NOTES TO CONSOLIDATED FINANCIAL STATEMENTS" in the most recent 10-K filing and answer the following questions. a. When will META recognize advertising revenue from impression-based ads? In the period when it signs an advertising contract with its clients, or in the period when ads are displayed on its platforms, or in the period when ads are clicked by its users? b. When will META recognize advertising revenue from action-based ads? In the period when it signs an advertising contract with its clients, or in the period when ads are displayed on its platforms, or in the period when ads are clicked by its users? c. What depreciation method does META use for Properties and Equipment? d. Did META change the estimated useful life assumption for some its long-term tangible assets in 2021? If so, what is the change and what is the impact on depreciation expense? e. Did META record material impairment charges for Properties and Equipment in the fiscal year 2021? f. What is the main reason for the change in META's goodwill in 2021? g. Did META record material impairment charges for Goodwill in the fiscal year 2021? h. What is the carrying value of acquired users as of December 31, 2021 and December 31, 2020, respectively?