I need help with this ASAP!

What would happen to the nutrients in an ecosystem if decomposers, such as bacteria, didn’t exist there?

For a comparative or experimental investigation, scientists often make a testable about a scientific question, and then they test it in the investigation. a.control b.hypothesis c.procedure d.system

Is there any species that went extinct in recent years due to natural causes (not caused by human interaction). if so, what caused it?