A. would not help and maybe make it harder to get accurate measurements.
b. would make more delta T which will improve its accuracy
c. will also increase delta T.
Not 100%, but I think it would be 0.0013 because the equation for Molarity is Moles of solute(Mol)/ Liters of solution(L)
I believe it would be agricultural because it is the most filled in on the graph.