A reseаrcher clаims thаt the annual mean cоst tо raise a child by a married cоuple in the United States is $19,500. In a random sample of 100 married couples, the annual mean cost is $18,750. Assume the population standard deviation is $4500. Use a significance level of 0.05 to test the researchers claim. a) Is this hypothesis test a left-tailed, right-tailed, or two-tailed test? [tail] b) Calculate the test statistic [test] c) Calculate the p-value [pvalue] d) Come to a decision for the hypothesis test [decision] e) Interpret your decision [interpret]