An analyst in a government ministry is interested in the average cost of textbooks per semester for a college student. A previous estimate suggests that the average cost of textbooks per semester is $700.The analyst wants to check this and conducts a random sample of 75 college students, asking them what their textbook costs were for the last semester. The sample results show an average cost of $756, with a standard deviation of $132.Is there evidence that average textbook costs per semester have increased for college students? You may assume that the standard deviation of all textbook costs is actually $132, and that the population data are normally distributed.
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