Whales entangled in fishing gear. Entanglement of marine mammals (e.g., whales) in fishing gear is considered a significant threat to the species. A study published in Marine Mammal Science (Apr. 2010) investigated the type of net most likely to entangle a certain species of whale inhabiting the East Sea of Korea. A sample of 207 entanglements of whales in the area formed the data for the study. These entanglements were caused by one of three types of fishing gear: set nets, pots, and gill nets. One of the variables investigated was body length (in meters) of the entangled whale.

a. Set up the null and alternative hypotheses for determining whether the average body length of entangled whales differs for the three types of fishing gear.

b. An ANOVA F-test yielded the following results:

F = 34.81, p - value 6 .0001. Interpret the results for a = .05.