Azygote develops into a multicellular organism through?

What is the number of moles of chemical units represented by 9.03x10^24? and how do i show work? (dumb it down )

If anyone would be able to me out with these three questions it would be these are from the chem 2202 course.

Which formula equation represents the burning of sulfur to produce sulfur dioxide? s(s) + o2(g) 4502(9) 2h2s(s) + 302(g) —> 2h20(0) + 2502(9) 4fes2+1102 —> 2fe2o3 + 8502 2802(g) + o2(9) v205 , 2503(9)