Answer:
NREM- 3 sleep
Explanation:
Basically we can divide sleep into two phases: REM (Rapid Eye Movement) and NREM (Non-Rapid Eye Movement). The state of NREM corresponds to 75% of the sleep period, being divided into four phases. Phases 1 and 3 being the easiest to wake up, while phase 2 allows the individual to have a certain difficulty in being awakened and phase 4 imposes great difficulty because it is a deep sleep.
Phase 3 can last from 15 to 40 minutes and represents a partially deep sleep, but which allows the individual to be awakened with a certain degree of ease. Since Gabe's friend was sleeping for 25 minutes and woke up with the sound of a laugh, we can say that Gabe's friend was in phase 3 of NREM sleep.