To plot the calibration curve, you need to prepare iron solutions with known concentration and measure their absorbance. You will obtain a STANDARD IRON solution contains 0.2500 g/L of pure iron. Pipet 25.00 mL of this standard iron solution into a 500 mL volumetric flask and dilute up to the mark with distilled water. And then, pipet certain amounts of this diluted solution into different flasks. How much of this diluted solution you need to pipet to have 0.00 mg of iron?