N- amount of data /S- standard deviation

An analysis for the determination of mercury in water gave the following results: Conc. ppb Hg No. Replicates Mean signal Devis 0.00 25 0.032 0.0080 2.00 0.0094 15.00 5 0.423 0.0065 10.00 5 0.702 0.0084 14.00 un 1.950 0.0110 Determine a. The equation of the line (Least squares). In addition, you must do the calculations using all The equations b. Calibrated Sensitivity c. The analytical sensitivity for 2.00 ppb and 10.00 ppb d. The concentration of a solution whose signal was 0.550 CV If we use the data from the previous problem for the standard addition method where 20 ml aliquots of the water sample were pipetted into 200 mL volumetric flasks. 0.00, 3.00.6.00, 12.00 and 18.00 mL of a standard solution containing 10.5 ppb of Hg were added and filled up to the mark. What concentration of Hg is in the water sample