17.contains plenty of salt. It is found in the seas and oceans. Seawater is also called. 18..
19.is found beneath the earth's surface. it comes from water that seeps into the ground. it is considered the cleanest water and contains plenty of dissolved minerals which the human body needs.
20. is also called surface water. This is found in opem but small bodies of watee loke rivers, lakes, creeks, and ponds. surface water comes mostly from rain.

Choices
Hard water
Sea water
fresh water
ground water​

17. Sea Water  

18. Salt Water (Hard Water)

19. Ground Water

20. Fresh Water

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.

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