They determine it because of the hypothesis. It changes during the investigation and the independent variable stays the same through the whole experiment.
Answer: Under normal ambient conditions water is less dense as a solid than as a liquid, so ice floats on water. Most materials are more dense as solids.
Explanation: When water freezes, the molecules do not stack into a close-packed structure. They form a relatively open, honeycomb-like arrangement.
Answer: A disease that is not contagious is called a noninfectious disease. These diseases are not caused by pathogens. Instead, they are likely to have causes such as lifestyle factors, environmental toxins, or gene mutations. Common types of noninfectious diseases include cancer, diabetes, and immune system diseases.
Explanation: hope this helps :)
True the human brain cannot perform 2 tasks that require high level brain function at once what is actually happening is that you are rapidly switching tasks
