In a study to determine how the calcium level of water affects respiration rate of fish, 360 fish in a sample were randomly divided into three tanks with different levels of calcium: low, medium, and high. The respiration rate of the fish, in beats per minute, was then measured. The dataset is in FishGills. and the two variables are Calcium and GillRate.

(a) Use technology to create side-by-side boxplots for gill rate in the three different calcium conditions. Describe the relationship between the two variables.

(b) Use technology to obtain comparative summary statistics for gill rate in the three different calcium conditions and give the mean and the standard deviation for the gill rates in each of the three calcium conditions.

(c) Is this study an experiment or an observational study?