Calibration graphs in instrumental analysis

1 Is the calibration graph linear If it is a curve, what is the form of the curve  

2 Bearing in mind that each of the points on the calibration graph is subject to errors, what is the best straight line (or curve) through these points  

3 Assuming that the calibration plot is actually linear, what are the errors and confidence limits for the slope and the intercept of the line  

5 What is the limit of detection of the method That is, what is the least concentration of the analyte that can be detected with a predetermined level of confidence  

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