Answer: because of the pandimic
it startExplanation: coronvires is the probelm over 4 years it started in 2019 to 2022 it even more year well never know.
You have to think of contaminated water if it were to evaporate it can effect the water cycle of an environment
A scientific experiment, in the form of the scientific model, is a testable model used to seek explanation for natural phenomena.