Explain how humans are solar powered (this is a 9th grade question)

How many variables are altered in a good experiment? a.1 b.0 c.2 d.3

Defend or refute the argument that the government has too large a presence in the agriculture industry.

Use the drop-down menu to match the following definitions to the corresponding terms. the total variety of organisms that live in the biosphere a group of organisms that breed and produce offspring that can breed all of the biotic and abiotic factors in an area