An internet service provider (ISP) has experienced rapid growth in the past five years. As part of its marketing strategy, the company promises fast connections and dependable service. To achieve its objectives, the company constantly evaluates the capacity of its servers. One component of its evaluating is an analysis of the average amount of time a customer is connected and actively using the Internet daily. A random sample of 12 customer records shows the following daily usage times, in minutes. Complete parts a through d below.

272 341 314 296 323 325 295 289 277 386 387 331a. Using the sample data, compute the best point estimate of the population mean for daily usage times for the lSP's customers. El minute(s) (Round to two decimal places as needed.) b. The managers of the ISP's marketing department would like to develop a 95% confidence interval estimate forthe population mean daily customer usage time. Because the population standard deviation of daily customer usage time is unknown and the sample size is small, what assumption must the marketing managers make concerning the population of daily customer usage times? CE The population distribution is approximately normal. if} The sample size is at least 30. i"? The population distribution is uniformly distributed. i"? The population distribution is unknown. 0. Construct and interpret the 95% confidence interval estima e for the mean daily usage time for the lSP's customers. The 95% condence interval estimate is minute(s) minute(s). (Round to two decimal places as needed. Use ascending order.) Interpret the confidence interval estimate. Select the correct answer below and fill in the answer box to complete your choice. (Round to two decimal places as needed. Use ascending order.) G A- Based on the sample data, the ISP can conclude that 95% of daily usage times are between minute(s) and minute(s). ['3' 5- Based on the sample data, with 95% condence, the ISP can conclude that the sample mean daily usage time is between minute(s) and minute(s). '3' 0- Based on the sample data, with 95% confidence, the ISP can conclude that the true population mean daily usage time is between minute(s) and minute(s). d. Assume that before the sample was taken, the ISP's marketing staff believed that mean daily usage time for its customers was 323 minutes. Does their assumption concerning mean daily usage seem reasonable based on the confidence interval developed in part c? because the confidence interval 323 minute(s)