Cold water holds more dissolved gas than warm water. Cold water also tends to collect in the lower levels of a lake.
However, in summer, oxygen levels in a lake can be highest
in the warm surface water of a lake. Explain why.

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

The instructions for making proteins come originally from

Explain why phospholipid molecules form a bilayer. (3 marks)