Are all major features on earths surface are caused by plate motion?

How has the scientific community addressed the safety of chemicals? a. chemicals are repeatedly tested, even those that have existed for a long time. b. existing chemicals are tested if they have never been tested before. c. chemicals are tested if they are suspected to have caused a problem. d. only new chemicals are tested.

How many moles of air are there in a human lung with a volume of 2.4 l at stp? explain your answer

How many moles of al3+ ions are in 1.25 moles of al2o3