You are analyzing a mixture for penicillin. To the mixture you add 10.0 mg of doped penicillin with a specific activity of 0.405 μCi/mg. From this mixture, you isolated only 0.35 mg of pure crystalline penicillin and it's specific activity was measured to be 0.035 μCi/mg. What was the penicillin content of the original sample?