How do scientists use weather to keep people safe

By predicting bad weather and keeping people safe during danger

Btw, i think you meant meteorologists.

i think that it is plants

the principles and empirical processes of discovery and demonstration considered characteristic of or necessary for scientific investigation, generally involving the observation of phenomena, the formulation of a hypothesis concerning the phenomena, experimentation to test the hypothesis, and development of a conclusion that confirms, rejects, or modifies the hypothesis.