Hi i need help its to much for my brain to think

What do you need to use in order to work as an environmental scientist? you need to use the scientific method and__ in order to work as an environmental scientist.

Why are human population trends difficult to predict?

According to the article, what valid claim came from the national research council? there is no association between fluoride exposure and increased cancer risk in humans. there is a possible link between fluoride exposure and increased cancer risk in humans. there is a definite link between fluoride exposure and increased cancer risk in humans.