Answer:
A variable is anything that can change or be changed. In other words, it is any factor that can be manipulated, controlled for, or measured in an experiment.
Sound waves, I'm pretty sure.
Polyatomic ion: a covalently bonded group of atoms that has a positive or negative charge and acts as a unit.
Answer:
- A ball does not move unlesss you kick it and it rolls aways
- a car stays still and is not in motion, unless you start the engine
- a pencil stays still on a table, it moves when you pick it up off the table
Explanation:
