How is the density of a substance calculated?

Iam in desperate need of with this !

According to the diagram; a) identify the anode of the cell and write the half-reaction that occurs there b) write the overall equation for the reaction that occurs as the cell operates c) calculate the value of the standard cell potential ,e cell. d)write the shorthand notation of the cell above e)indicate the flow of the electrons on the diagram

Astudent uses universal ph paper to find the ph of three solutions . solution a has a ph of 5 solution b has a ph of 11 and solution c has a ph of 7 identify which solution is acidic which solution is neutral and which solution is basic