According to a social media blog, time spent on a certain social networking website has a mean of 20 minutes per visit. Assume that time spent on the social networking site per visit is normally distributed and that the standard deviation is 7 minutes. Complete parts (a) through (d) below. (E) a. If you select a random sample of 36 sessions, what is the probability that the sample mean is between 19.5 and 20.5 minutes? 0.32 (Round to three decimal places as needed.) b. It you select a random sample of 36 sessions, what is the probability that the sample mean is between 19 and 20 minutes? 0.304 {Round to three decimal places as needed.) c. If you select a random sample 0! 144 sessions. what is the probability that the sample mean is between 19.5 and 20.5 minutes? 0.60? (Round to three decimal places as needed.) :1. Explain the difference in the results of (a) and (c). The sample size in (c) is greater than the sample size in (a), so the standard error of the mean (or the standard deviation of the sampling distribution) in (c) is than in (a). As the standard enor values become more concentrated around the mean. Therefore, the probability that the sample mean will fall in region that includes the population mean will always decrease when the sample size increases