How many moles of N are in 0.247 g of N2O

When would a bouncy ball have the most potential energy

Once similarity and one difference between a mixture of elements and a mixture of compounds

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