After about five minutes of searching for a seat, I finally spotted an empty seat right next to one of my friends. ... I had only been there for fifteen minutes, but it felt like I had been there for hours. ...

• Word Count: 783
• Approx Pages: 3
• Grade Level: High School

After spending about twenty minutes in stage 4, they return to stage 1 and progress back to stage 4. ... The REM will usually begin ninety minutes after sleep is initiated and will last roughly ten to fifteen minutes (Davidmann, 1998). It is during the ten to fifteen minutes that dreams occur. ...

• Word Count: 3048
• Approx Pages: 12
• Grade Level: High School

NREM sleep begins after the first 90 minutes of sleep. The entire NREM sleep process takes in between fifty and seventy minutes. ... Stage 1 usually only lasts for a few minutes, while stage 2 lasts for about fifteen to twenty minutes. Stages 3 and 4 can last up to twenty to forty minutes. ... After the first 90 minutes of sleep, you continuously cycle between NREM and REM sleep. ...

• Word Count: 2563
• Approx Pages: 10
• Grade Level: High School