Multicellular? or do you mean animals?
You can tell if matter is conserved if the substance changes . If the substance changes then matter has been conserved .
Answer:
Scientists mostly gain new knowledge through direct observation and applying the scientific method. They would start with a hypothesis and test it, then change it or confirm it. Others would test their confirmation from one point, while the third group would test what the second said. And so on and so forth.
Explanation:
Because the prefrontal cortex is still developing, teenagers might rely on a part of the brain called the amygdala to make decisions and solve problems more than adults do. The amygdala is associated with emotions, impulses, aggression and instinctive behaviour.