An environmental chemist working for the Environmental Protection Agency (EPA) was directed to collect razor clams from a heavily-contaminated river superfund site and analyze them for their Cd^2+ content using graphite furnace atomic absorption spectrometry (GFAAS). The chemist dried the dams at 95 degree C overnight and ground them in a scientific blender, resulting in approximately 50 g of homogenized dry weight. A representative 57.95 mg sample was taken from the approximately 50 g of dry material and dissolved in 100.0 mL of 0.1 M HCl to create a sample solution. Using the method of standard additions, the chemist prepared five standard solutions in 100.0-mL volumetric flasks, each containing 5.00-mL aliquots of the sample solution. Varying amounts of a 98.0 ppb (mu g/L) Cd^2+ standard were added to each of the flasks, which were then brought to volume with 0.1 M HCl. The Cd^2+ content of the solutions was then analyzed using GFAAS, resulting in the following absorbance data. Determine the amount of Cd^2+ per gram of dry clam. Express your final result as milligrams of Cd^2+ per gram of dry clam.
