A water sample is analyzed for a pollutant by the standard addition method . four solutions are prepared,each with a 10.00 ml aliquot of the water sample and varying amounts of a 10 ppm standard solutions of the pollutant. Each of the resulting solutions was diluted to a final volume of 50.00. The absorbance of each solution was then measured at 254 nm.

Solution Volume of water sample (ml) Volume of standard (ml) Absorbance

1 10.00 0 0.062

2 10.00 10.00 0.211

3 10.00 20.00 0.407

4 10.00 30.00 0.555

What is the ppm concentration of the pollutant in the original water sample?