In an experiment, the variable that is changed and tests is called the variable.

Look at the following answer choices and determine which belongs in the both category. testable, can be disproven explains natural phenomena, has evidence to support it prediction, tentative, one or more scientists working together well established, many different scientists working independently, highly reliable

Ascientist is conducting an investigation that involves water, silver, carbon dioxide, and oxygen gas which group of statements best describes all of the materials he is using in the investigation?

Which of the following is the earliest era of earth's geologic time scale? cenozoic mesozoic precambrian paleozoic