Three important plant experimentation discoveries by scientists within the last 300 years are:

Three important plant experimentation discoveries by scientists within the last 300 years are: Nicholas de Saussure was the first chemist to begin quantifying the process of photosynthesis. Jan Baptista's experiments showed that the loss of soil mass < gain of plant mass and that the gain of plant mass is related to water. Ingenhousz found that air would be purified only when the sun's energy and green plants worked together in the system.

The answer should be geothermal i hope i’m right message me if i’m wrong and i’ll change my answer and fix it for you