Well # # Drops of Iron Sulfate # Drops of Sodium Hydroxide
 A1 5 45 
 A2 10 40 
 A3 15 35 
 A4 20 30 
 A5 25 25 
 A6 30 20 
 B1 35 15 
 B2 40 10 
 B3 45 5
that's for B, because it says "Iron Sulfate". 
which is this equation: FeSO4 (aq) + 2NaOH (aq)  Fe(OH)2 (s) + Na2SO4 (aq) 
FeSO4 (aq) + 2NaOH (aq)  Fe(OH)2 (s) + Na2SO4 (aq) 
ratio of FeSO4:NaOH is 1:2, 
so you need to moles of NaOH for every mole of FeSO4.
A1-A6 had precipitate, though less ppt every time. This corresponds to the decrease in the number of NaOH drops At A2 10/1:40/2 the stoichiometric ratio is equal, so you should've seen the post ppt present. But looking at the picture it doesn't look right. I think you might've labelled them wrong, or there is an error somewhere. This fits micro-plate A better.