Suppose a company is interested in determining whether there is a significant difference in the mean monthly sales revenue between two different product lines. The company randomly samples 10 months of sales data for each product line and obtains the following results:

Product Line A:
nA = 10, x?A = $15,000, sA = $2,500

Product Line B:
nB = 10, x?B = $18,000, sB = $3,000

a) State the null and alternative hypotheses for testing the difference in means between the two product lines.

b) Calculate the pooled estimate of the population variance assuming equal variances.

c) Calculate the test statistic for testing the difference in means between the two product lines using a 5% significance level.

d) Determine the critical value for the test statistic and state the decision rule.

e) Make a decision regarding the null hypothesis and interpret the result.

f) Calculate the 95% confidence interval for the difference in means between the two product lines.

g) Interpret the meaning of the confidence interval in the context of the problem.

h) Determine the sample size required for each product line if the company wants to estimate the difference in means with a 95% confidence interval that has a margin of error of $1,000.