A scientist wants to estimate the mass of an atom . What information can be used to do this

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

Which part of the cell is affected by the movement of molecules through diffusion, osmosis and active transport?

How does the nervous system affect the excretory system?