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A real estate agent claims that a house's appraisal value is higher than its selling price on average in a Melbourne suburb. She collected the selling price and the appraisal value for 25 recently sold houses in this suburb. The mean and standard deviation of the selling price, the appraisal value, and the differences between the two (Differences : SellingAppraisal) are presented in Table 1. Table 1: House price (in thousands) Selling Appraisal Difference Mean 861 875 14 Standard Deviation 104 78 23 1. Identify the sampling design used to obtain the data in Table 1. 2. The standard deviation of the differences (between selling price and appraisal value) is much smaller than the standard deviation of selling price or appraisal value. Briey explain why. 3. Assume the differences are normally distributed. Use the p-value approach in hypothesis testing to evaluate the real estate agent's claim at the 5% signicance level. Write down the ve steps of hypothesis testing (use appropriate Excel functions to conduct you analysis but do not copy/ paste a screenshot of your Excel output). Present your test statistic and p-value rounded to three decimal places