E3.1 (L01), Chloe Davis has prepared the following list of statements about the time period assumption. 1. Adjusting entries would not be necessary if a company's life were not divided into artificial time periods. 2. The IRS requires companies to file annual tax returns. 3. Accountants divide the economic life of a business into artificial time periods, but all transactions affect only one of these periods. 4. Accounting time periods are generally a month, a quarter, or a year. 5. A time period lasting one year is called an interim period. 6. All fiscal years are calendar years, but not all calendar years are fiscal years