In an evaluation of a method for the determination of fluorene in seawater, a synthetic sample of seawater was spiked with 50 ng ml −1 of fluorene. Ten replicate determinations of the fluorene...

In an evaluation of a method for the determination of fluorene in seawater, a synthetic sample of seawater was spiked with 50 ng ml⁻¹
of fluorene. Ten replicate determinations of the fluorene concentration in the sample had a mean of 49.5 ng ml⁻¹
with a standard deviation of 1.5 ng ml⁻¹

.

Calculate the 95% confidence limits of the mean. Is the spiked value of 50 ng ml⁻¹
within the 95% confidence limits?