When one observes the phase of matter of water, one observes of matter

Liquid water turns into water vapor at which step in the water cycle? a. precipitation o b. water run off c. evaporation d. condensation

What is thought to have caused the mass extinction at the end of the cretaceous period?

Creation of an unnaturally uniform sample to represent a diverse populationcan be avoided by: a. including only willing b. asking another scientist for .c. choosing only identical participants.d. selecting individuals at random.