A researcher is interested in determining the detection and quantitation limits of a method for the detection of thallium. Ten method blanks gave the dimensionless instrument readings: 81.9, 46.1, 38.9, 50.9, 95.9, 36.7, 88.7, 74.3, 41.3, and 82.1. Ten samples containing a low concentration of thallium near the detection limit had a mean reading of 164.7. The slope of the calibration curve is 2.77 10 M-'. Estimate the signal and concentration detection limits and the lower limit of quantitation for thallium. signal detection limit: 233.7 Incorrect concentration detection limit: 2.49 x108 M lower limit of quantitation: 8.30 x10-8 M