To calculate the concentration of iron Fe in the water sample, we can use the Beer-Lambert Law, which states:A = * c * lwhere A is the absorbance, is the molar absorptivity coefficient, c is the concentration of the solution, and l is the path length of the cuvette usually 1 cm .We are given the absorbance A as 0.52 and the molar absorptivity coefficient as 1.20 x 10^4 M^-1 cm^-1. We need to solve for the concentration c and assume the path length l is 1 cm.Rearranging the equation to solve for c:c = A / * l Plugging in the given values:c = 0.52 / 1.20 x 10^4 M^-1 cm^-1 * 1 cm c = 0.52 / 1.20 x 10^4 c = 4.33 x 10^-5 MThe concentration of iron Fe in the water sample is approximately 4.33 x 10^-5 M.