Two different laboratories measured the concentration of a chemical (in mg/L) in the same type of water sample. Their results are:
Laboratory A: 4.2, 5.1, 3.9, 4.8, 5.0, 4.5, 4.3, 4.7
Laboratory B: 4.9, 5.8, 4.0, 4.1, 5.7, 4.3, 3.8, 5.2
Using these observations, answer the following.
(i) For Laboratory A, calculate the mean, variance, and standard deviation.
(ii) For Laboratory B, calculate the mean, variance, and standard deviation.
(iii) Based on the standard deviations obtained, state which laboratory produced more consistent measurements and justify your answer.