Please choose the correct ending to complete the given sentence: Health: [header] How to know how much sleep you need [title] Perform a simple sleep test. [step] It may take more than one night to determine the results of this test. [substeps] The next opportunity that you have to " sleep in " for a few days is your chance to perform this test.

Ending1: You may need several nights in a row to get the best results. Step one of the test is to go to bed at a reasonable time. Ending2: Make sure that you're doing it on schedule, otherwise you run the risk of the test taking twice or more times. If you're tired all the time, your body will get the message from the test that they will not be able to detect changes in your sleep patterns. Ending3: The average night is 1 am, and you go to bed and wake up at the same time each morning. Test at an hour or two before your scheduled bedtime. Ending4: In most cases, it is best to do it the next night. For very low resolution tests, it can be a combination of its rays occurring from the sun or an ultraviolet (uv) light source.

Answer format: ending1/ending2/ending3/ending4