In an environmental study into the wildlife in two comparable lakes, samples of small frogs were taken from each. The frogs were of the same species and all of similar ages, each being weighed. Their weights (in g) are given below:



Part a)
Which graphical method would best display the above data?

A. Side-by-side boxplots
B. A histogram
C. A scatter plot
D. Two histograms plotted on the same axis
E. A stem-and-leaf plot


Part b)
If using the Wilcoxon rank sum test on the above data, which of the following best describes the null hypothesis?

A. The medians of the distributions of weights of frogs in the two lakes are equal.
B. There is no correlation between the weights of the frogs in the two lakes.
C. There is no difference between the distributions of the weights of the frogs in the two lakes.
D. The sample means of the weights of the frogs in the two lakes are equal.
E. The weights of the frogs is independent of which lake they were chosen from.


Part c)
In conducting a hypothesis test here, would you take a one-sided or two-sided alternative?

A. One-sided
B. Two-sided


Part d)
Provide the P-value of your test to 3 decimal places.


Part e) Would you reject or not reject your null hypothesis at the 5% significance level?

A. Not reject
B. Reject