I’ll give a lot of points just please help and has to be the correct answer

The ocean continued to shrink until, about 270 million years ago, the continents that were ances tral to North America and Africa collided. Huge masses of rocks were pushed west ward along the margin of North America and piled up to form the mountains that are now the Appalachians. Well, mountains are limited in their theoretical height by several processes. First is called isostasy the bigger a mountain gets, the more it weighs down its tectonic plate, so it sinks lower. The second is called glacial buzzsaw the taller and colder a peak, the faster snow and ice will wear it down/away.

Explanation:

Hope that helps you.

its 42

i say its d?

americans began to notice growing differences between the northern and southern sections of the country. there were more people living in cities in the north, which made it more urban. more people lived on farms in the south, which made it more rural. while many people were farmers in the northern states, there were now other ways to make a living, such as working in mechanical cotton gins factories manufacturing cloth, tools and other goods. people in the north supported high tariffs on goods imported from europe because the extra cost encouraged people to “buy american” instead. in the southern states, planters did not like tariffs because they sold most of their production to europe and bought their tools from there as well. southerners believed the protective tariff was something that only northern factory owners keep their profits high. so the southern politicians came up with an idea. they would opt out. they would simply ignore the protective tariff. it was ‘null and void’ in south carolina. the state would not collect the taxes on goods imported into south carolina, no matter what the president said they had to do. this decision led to the nullification crisis.