Aresearcher used hplc to examine a bicomponent mixture containing 1.22 mg/l of compound a and 1.31 mg/l of compound b, which was added as an internal standard. this mixture produced peak areas for compounds a and b of 10919 and 5379 , respectively. using the above information, determine the response factor (f).

after establishing f, the researcher prepared a solution by combining 8.18 mg of b with 10.00 ml of an unknown solution containing only a and then diluted it to a final volume of 50.00 ml. the sample was examined using hplc and peak areas of 6065 and 9111 were observed for a and b, respectively.

determine the concentration of a (mg/ml) in the unknown solution.