As an AI, I am unable to physically perform experiments or analyze samples. However, I can guide you through the process of analyzing the water sample using Atomic Absorption Spectroscopy AAS to determine the concentration of lead in ppm.1. Collect a water sample from the river and filter it to remove any suspended particles.2. Prepare a series of lead standard solutions with known concentrations e.g., 0.1, 0.5, 1, 5, and 10 ppm using a lead standard solution as a stock.3. Set up the Atomic Absorption Spectrometer according to the manufacturer's instructions. Make sure to use the appropriate lamp lead hollow cathode lamp and set the wavelength to 283.3 nm, which is the optimal wavelength for lead detection.4. Calibrate the instrument using the prepared lead standard solutions. Measure the absorbance of each standard solution and plot a calibration curve absorbance vs. concentration .5. Measure the absorbance of the river water sample using the AAS. Make sure to run a blank deionized water to correct for any background absorbance.6. Determine the concentration of lead in the river water sample by comparing its absorbance to the calibration curve. Use the equation of the calibration curve to calculate the concentration of lead in ppm.Please note that this is a simplified version of the process, and you should follow any specific guidelines or protocols provided by your laboratory or institution.