Someone help with these questions??

What is the percentage by mass of silicon (si) in iron aluminum silicate (fe3al2(sio4)3)?

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

How many moles of cu are needed to react with 5.8 moles of agno3? cu + 2 agno3 → cu(no3)2 + 2 ag