The weekly sales at two movie theaters were recorded for a random sample of 25 weeks. A 95 percent confidence interval for the difference in mean weekly sales for the two movie theaters was calculated as ($1,288,$2,586). With all else remaining constant, which of the following would have resulted in a confidence interval narrower than the calculated interval? A sample size less than 25 A sample size less than 25 A A sample size greater than 25 A sample size greater than 25 B An increase to 99 percent confidence An increase to 99 percent confidence C A sample mean greater than $1,937 A sample mean greater than $1,937 D A sample mean less than $1,937