Colby had a big work deadline and stayed up most of the night to complete it. on the way to work, he wondered how he was going to make it through the day feeling this tired. by about 11 a. m., he felt much better and far more awake. this is likely due to the in his brain.

   Decreased levels of melatonin

Explanation:  Melatonin is a substance that is excreted at night and by which the brain sends signals that one should sleep, that is, a man / woman is feeling sleepy. When melatonin secretion decreases, the alertness increases, as is the case with Colby. Melatonin levels decrease at the base of the brain signal regardless of whether or not Colby slept enough the previous night. Feeling tired will induce some other receptors and consequent signals from the brain, but a natural decrease in melatonin throughout the day occurs normally.

carefully examine the map above. based on your knowledge of colonialism in africa, the area attributed to belgium on this map is most likely the democratic republic of the congo.

the correct answer is the following is a list of inventions made in the medieval islamic world, especially during the "islamic golden age" (8th to 13th centuries),[1][2] as well as the late medieval period, especially in the emirate of granada and the ottoman empire.

science and technology in the islamic world adopted and preserved knowledge and technologies from contemporary and earlier civilizations, including persia, india, china, and greece-roman antiquity, while making a number of improvements and innovations.