Compounds are made of two or more atoms of different elements, such as water (H2O) and methane (CH4). Atoms are not drawn to scale. Molecules of compounds have atoms of two or more different elements.
Open system is a system in which mass or energy can be lost to or gained from the environment. In this case, water and power come from external sources best explains why a washing machine would be considered an open system.
Quantitative is the amount of something. Qualitative is the degree of excellence of something.
Firework exploding. Thank you :)
Just letting you know many people can't help you if you don't post a picture of the food web!