Which gas is not produced by volcanic eruptions?

Which of the following is an abiotic factor in an ecosystem? a. bacteriab. airc. niched. grass(abiotic=non-living) me !

Dr. arenas is a scientist who has been trying to determine if increasing pressure will increase the sound that occurs when two chemicals explode. it measures the volume of the sound that occurs at the minimum pressure at which the explosion will occur. it then increases the pressure and measures the volume of the explosions that occur. what kind of investigation is the scientist conducting?

Explain how negative feedback caused the changes in plasma glucagon concentration observed during the experiment.