Xi needs to stay awake another hour to study for his english final, so he drinks several cups of cola. when he’s done studying, he finds that he can’t sleep even though he wants to, he feels agitated, his muscles twitch, his heartbeat is irregular, and he feels nauseated. what is causing xi to feel this way?

caffeine.

Explanation:

When Xi consumed several cups of coffee to stay wake for another hour.Coffee contains caffeine.Since caffeine is psychoactive drug and it is legal also unlike other psychoactive drugs.You feel more energetic.It acts as a central nervous system stimulant and when it reaches the brain it causes alertness and you will feel more awake.But Xi consumed more than he needed hence he was not able to go to sleep.

answer; acquired mainly during early childhood;

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