DO stands for dissolved Oxygen in the water. Tank 1 Tank 2 Tank 3 Tank 4 Tank 5

Initial DO 10 ppm 10 ppm 10 ppm 10 ppm 10 ppm

Amount of organic waste 0 g 10 g 20 g 30 g 40 g

DO after one week 10 ppm 10 ppm 8 ppm 5 ppm 0 ppm

Based on this table what is the main purpose for the experiment?to determine how much oxygen the algae can produce

to collect data to determine how waste in water can be useful

the DO doubles each week

to determine that initial DO is not important

to observe the effect of organic wast on DO

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.