Dna molecules are replicated during what part of the cell cycle

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

Which of the following observations indicates that there is a small, dense, positively charged part in the center of an atom? some uncharged particles are scattered by a gold foil. all uncharged particles are attracted towards a gold foil. all positively charged particles pass straight through a gold foil. some positively charged particles bounce back from a gold foil.

Use the periodic table to complete this equation that represents nuclear fission processesun - ba c 3 n