Element Name and How Many Atoms (Number) H2

Which statement correctly identifies the scientific question and describes why the question is scientific? question 1 refers to the supernatural.question 2 reflects a moral or social value.question 3 refers to something that can be measured.question 4 reflects a question that can’t be observed.

Calculate the percent composition by mass of each element in al(oh)3. use at least three significant figures.

Athe top of a hill, an athlete on a skateboard has x joules of mechanical energy. how much mechanical energy will she have at the bottom of the hill? ignore the effects of friction.