I think the correct answer would be D. The brain waves changes from stage 1 to stage 2 as a person sleeps in a way that these waves become slower. That is, the amplitude would decrease since less activity is done and the frequency would decrease as well since less wave passes per second.
Answer:
the 19th-century doctrine or belief that the expansion of the US throughout the American continents was both justified and inevitable.
Explanation:
Answer:
I would say - Check your tire pressure every day.
