I need help with question 4

*Please choose correctly*

Thank you

In saturated organic compounds, all the bonds between carbon atoms are called?

All of the following are part of the biosphere except

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.