Nitrates are organic compounds that are a main ingredient in fertilizers. When those fertilizers run off into streams, the nitrates can have a toxic effect on fish. An ecologist studying nitrate pollution in two streams measures nitrate concentrations at 42 places on Stony Brook and 42 places on Mill Brook. The parallel dotplots display the data. Which of the following is a correct comparison of the distributions of nitrate concentration in these two streams? Both distributions appear to be right-skewed.

Neither distribution of streams has any apparent outliers.

The distribution of nitrate concentration for Mill Brook is more variable than the Stony Brook distribution.

The distribution for Mill Brook is single-peaked while the distribution for Stony Brook has two peaks.

The median nitrate concentration for the two streams are about the same.