The pH of a liquid is a measure of its acidity or alkalinity. Pure water has a pH of 7, which is neutral. Solutions with a pH less than 7 are acidic while solutions with a pH greater than 7 are basic or alkaline. The dataset FloridaLakes gives information, including pH values, for a sample of lakes in Florida. Computer output of descriptive statistics for the pH variable is shown:

(a) How many lakes are included in the dataset? What is the mean pH value? What is the standard deviation?
(b) Use the descriptive statistics above to conduct a hypothesis test to determine whether there is evidence that average pH in Florida lakes is different from the neutral value of 7. Show all details of the test and use a 5% significance level. If there is evidence that it is not neutral, does the mean appear to be more acidic or more alkaline?
(c) Compare the test statistic and p-value you found in part (b) to the computer output below for the same data:

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Descriptive Statistics: pH N* Variable N Mean SE Mean StDev 1.288 pH 0.177 53 0 6.591 Q1 Median Minimum Q3 Maximum 3.600 5.800 6.800 7.450 9.100 One-Sample T: pH Test of mu = 7 vs not = 7 Variable Mean StDev SE Mean pH 53 6.591 1.288 0.177 95% CI (6.235, 6.946) -2.31 0.025