Explanation:
pure substances are those substances which are made up of one elements
mixture that those substances which are made by more than two or three elements
Answer: The scientific method. When conducting research, scientists use the scientific method to collect measurable, empirical evidence in an experiment related to a hypothesis (often in the form of an if/then statement), the results aiming to support or contradict a theory.
Explanation:
Ok so 40 percent of 3000 grams which is 3 kg is 1200 grams
So you would need 1.2kg or 1200 grams to make a 40% solution