¿Qué elementos consideras que deben ser preservados y cuales deberían ser cambiados y por qué?

Pollution from a factory that produces cleaning products is an_

When should you question a sources credibility

If the age of the lowermost layer of a rock sample is more than 2 million years, which of the following could be the age of the upper layers? less than 1 million greater than 3.5 million between 2 million and 3 million between 3 million and 3.5 million