If ethan experiences a big jolt of cortisol due to a stressor late in the evening, how will his sleep likely be affected?

The answer is "He likely will have difficulty falling asleep and may wake frequently during the night."

In the event that you encounter a big jolt of cortisol because of a stressor late at night, getting the chance to rest will be hard, regardless of whether you are drained temperament and rest can both influence craving, in light of pressure related hormones, fat cells act in an unexpected way, developing in both size and number.