Please study thoroughly the Diagram that opens up from the link below. It is believed that many of the questions you've sought answers for will be found by so doing.
NB After clicking on the link if you choose ‘Open’ your Web Browser's Toolbars may overlap Excel’s Toolbars. If this happens you may need to choose View/ Toolbars and then tick Standard. The better option however is to choose ‘Save’ and then save the Diagram to a location of your choice. You can then print it out and study it in your own time.
The Diagram was drafted using Excel 2003. Please use the Zoom % function on your toolbar to view the individual parts of the Diagram in closer detail.