1. Lack of sleep
a. improves memory and concentration.
b. may cause irritability.
c. may cause weight loss.
d. enhances the immune system.
2. Which statement about sleep is correct?
a. People cannot learn to sleep better.
b. People dream during REM sleep.
c. Drinking alcohol helps most people sleep better.
d. Snoring may be a symptom of insomnia.
3. Normal shyness can usually be overcome by
c. retail therapy.
d. working at improving social skills.