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?
a. caffeine
b. insomnia
c. narcolepsy
d. sugar

Slow down transpiration by the stomata question 9 options: a guard cells; closing b chloroplasts; closing c guard cells; opening d chloroplasts; opening

Aremote community desperately needs more electrical energy. it is located in an area with the following characteristics: average wind speed of 15 – 20 km/hr some medium-sized rivers with slow-moving currents few coal deposits some oil exploration being conducted within 400 miles based on the above information, which energy source would be the most economical and safest for the community to pursue? a. fossil fuel b. hydroelectric c. nuclear d. wind

How do specific cell structures and organelles contribute to maintaining homeostasis in the cell?