C. Identify whether the following are effects of Earth's rotation or revolution. Write RO for the effects of Earth's rotation or RE for Earth's revolution. 1. Winter starts on December 21 or 22. 2. Places facing the Sun experience daytime. 3. Places facing away from the Sun experience night time. 4. The Earth's motion on its axis causes day and night. 5. Summer begins in the northern hemisphere on June 21 or 22. 6. On September 23, the day and night are again of equal length. 7. Twice a year, the daylight and night time periods are of equal length. 4​