Describe how you would prepare the following solutions from water and the solid solute:

a. 1.85 L of an aqueous solution that is 12.0% KBr by mass and has a density of 1.10 g/mL;

b. 1.20 L of a solution that is 15.0% Pb(NO3)2 by mass and has a density of 1.19 g/mL.