Crab spiders hiding on flowers. Refer to the Behavioral Ecology (Jan. 2005) field study on the natural camouflage of crab spiders, presented in Exercise 2.38 (p. 47). Ecologists collected a sample of 10 adult female crab spiders, each sit ting on the yellow central part of a daisy, and measured the chromatic contrast between each spider and the flower.
The contrast values for the 10 crab spiders are reproduced in the table and saved in the SPIDER file. Recall that a contrast of 70 or greater allows bird predators to see the spider. Consider a test to determine whether the population median chro matic contrast of spiders on flowers is less than 70.
Based on Thery, M., et al. "Specific color sensitivities of prey and predator explain camouflage in different visual systems." Behavioral Ecology , Vol. 16, No. 1, Jan. 2005 ( Table 1 ).
a. State the null and alternative hypotheses for the test of interest.
b. Calculate the value of the test statistic.
c. Find the p -value for the test.
d. At a = .10, what is the appropriate conclusion? State your answer in the words of the problem.

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