What forces are responsible for anticlines and synclines

Calculate the number of molecules present in 0.750 mol of mgo.

When a septic tank backs up a goes in to clean it out

Which best describes the present-day universe? opaque, expanding very slowly, stars produce heavy elements transparent, expanding at an accelerated rate, stars produce heavy elements opaque, expanding at an accelerated rate, stars produce only hydrogen and helium transparent, expanding very slowly, stars produce only hydrogen and helium