Is there supposed to be a picture?
Archean and Proterozonic which are both broken into early middle and late periods
Answer:
A control group setup in an experiment is used to see if there are other variables in play during the experiment. Say I was to test which type of blood is a shark's favorite, my control would be putting red paint in one of the set ups to see if the shark is just interested in the red color of blood, instead of the other types of blood.
Explanation:
The first colorimeter is precise, but it is not accurate. It seems to have a zero error of -5.
We can conclude its precision because the readings are closely grouped, but its lack of accuracy is due to its variation from the actual value. Moreover, the variation is consistently of 5 points lower than the actual value, so its zero error may be -5.
The second colorimeter may be referred to as being accurate.
