Answer:
I think it is 4 but, im not sure
Answer:
This should help
Step-by-step explanation:
An observation study is where nothing changes and you record what is seen. An experimental study you have a control group and a testable group.
The answer would be: .C. The groups in an experiment are chosen at random, but not in an observational study.
I think formula is y2-y1 divided by x2-x1 so if im correct
-5/-4