Lisa wants to estimate a confidence interval for the average number of squirrel nests per acre in Yellowstone. There are 1000 acres in the Preserve, so Lisa wants to take a sample of acres from the park. From a study in a similar park he knows the standard deviation of the nests/acre is 5. What sample size should Lisa choose if she wants his estimate to have a half width of 1.1 nests? Use = 0.05.

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