Surveys of dog owners in two adjacent towns found the average veterinary-related expense total for dog owners in town A during the preceding year was $240, with a standard deviation of $55, while the comparable results in nearby town B were $225 and $32, respectively. Assuming a sample size of 30 dog owners surveyed in each town, use a z-test and the 0.05 level of significance in determining whether the population means might actually be the same. Determine and interpret the p-value for the test; then construct and interpret the 95% confidence interval for the difference between the population means.
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