Graduated Cylinder. A graduated cylinder measures volumes of liquids.
I don’t understand what u say
First, he should measure how long it takes for the liquid to become clear if X and Y are mixed together. Then, he should measure how long it takes if he also adds substance A to X and Y. He will find out if substance A is a catalyst. hope this helps :)
7. Succession, 6. Extinction, 5. Niche, 3. Ecosystem, 2. Population, 1. Habitat, 4. Environment, 8. Community
