Answer:
A gas-powered lawn mower is a complex machine because for it to function it does more than one motion. For example, it has a wheel and axle system so it can move when powered. And it has a system of simple machines and other parts that are put together to accomplish the task of cutting grass.
Explanation:
A molecule is made of more than one atom of differing elements that can be simplified while an element cannot be simplified because it is only one atom of one type of element.
The level most commonly meant by the term biodiversity is the species level.