Cobalt is often added to steel in order to increase its hardness. The cobalt content of 5 different steel samples was measured by titration and by spectroscopy (Table 2). Table 2: Cobalt content (in...

Do the two analytical methods provide results that are significantly different at the 95% confidence interval? Justify fully, showing all calculations, logic etc

Extracted text: Cobalt is often added to steel in order to increase its hardness. The cobalt content of 5 different steel samples was measured by titration and by spectroscopy (Table 2). Table 2: Cobalt content (in mg L) in 5 different steel samples. Sample Titration Spectroscopy 1 134 135 144 156 3 126 137 4 125 137 137 136