answer a showing how its done on excel

answer b and c also

please answe asap and correctly

3) (30 marks] Standard aqueous solutions of FeCl2 are examined in a UV-Vis spectrometer. They yield the following absorbances at a given wavelength: Concentration, mg ml1 0 2 4 6 8 10 Absorbance 0.045 0.790 1.505 2.360 2.885 3.066 Blank sample number Absorbance 1 0.03 2 -0.02 3 -0.01 4 0.02 5 -0.02 6 0.03 -0.01 (a) Determine the unweighted least regression equation of the line and product-moment correlation coefficient, r, by processing the data in Excel. (b) Comment on the suitability of the linear regression fit to this data, providing evidence to support your opinion. (c) Assuming a linear correlation, calculate the concentration of a sample with an absorbance of 1.230