Why is the fossil record incomplete? choose all that apply.
not all organisms are fossilized.
not all scientists believe in the fossil record.
not all fossils survive.
not all fossils are found.

Explanation:

The most direct way to determine the age of a species is to observe in the fossil record what was the first occurrence of this species. The biggest problem is that the fossil record is very incomplete, because many times organisms decompose before being fossilized, and many fossils have never been found. In short, we can say that the fossil record is incomplete because not all organisms are fossilized, not all fossils survive and not all fossils are found. Moreover, the fact that one finds fossils of a species from a certain age does not mean that such a species originated at that time in geological history. It may be that records of the species's presence in previous ages have been lost.

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.

c) 50% there are four chromosomes. after crossing over, 2 of the four have been changed. that means any gamete has a 2 in 4 chance or 50% chance of receiving the mutated chromosome.