How does nicotine affect the respiratory system answers?

Researchers randomly divide participants into groups. each group takes a different amount of omega-3 fatty acid supplements daily for a month. one group receives a placebo. the researchers measure the impact on cholesterol levels in the blood. what is the purpose of random assignment in this experiment? a, to produce treatment groups with similar characteristics b, to ensure that all people with high cholesterol have an equal chance of being selected for the study c, to increase the accuracy of the research results and prevent skewness in the data

If you have a difficult time knowing where your hand is without looking at it you may be having a problem with your what ?

In the ocean why are the greatest amount of primary producers found in the epipelagic zone and how does that affect biodiversity