The Random Variable X Is Normally Distributed with Mean of 80

question 88

Multiple Choice

The random variable X is normally distributed with mean of 80 and variance of 36.The 67th percentile of the distribution is

• A)72.00
• B)95.84
• C)90.00
• D)82.64

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Definitions:

Sleep Spindles

Brief bursts of brain activity detectable in EEG recordings during stage 2 of non-REM sleep, associated with learning, memory consolidation, and protection of sleep.

Stage 2 Sleep

A part of the sleep cycle characterized as the first actual stage of non-REM sleep, involving slowing heart rate and brainwaves, and preparation for deep sleep.

K Complexes

Specific brainwave patterns observed during stage 2 sleep, characterized by a brief surge of high voltage brain activity.

Paradoxical Sleep

Another term for REM (Rapid Eye Movement) sleep, characterized by active brain waves, flaccid muscles, and vivid dreams.