Scientific investigation questions please help!

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

How does an angiosperm prevent self pollination

Which of these is true for bacteria because they are prokaryotic cells? a. they can engulf body cells in order to make memory cells. b. they must invade viruses in order to reproduce. c. they are much larger than eukaryotic body cells. d. they can reproduce on their own outside of other cells.