It currently takes user a mean of 15 minutes to install the most popular computer program made by Roadtec a software design a company after changes have been made to the program the company executives wants to know if the new mean is now different from the 15 minutes so that they can change their advertising accordingly a simple random sample of 20 new customers are asked to time how long it takes for them to install the software the sample mean is 14.1 minutes with a standard deviation of 1.9 minutes perform a hypothesis test at the 0.05 level of significance to see if the mean installation time has changed State the hypothesis and the alternative hypothesis what is the test statistic what is the critical value what is the P value and what is the conclusion at the 0.05 level of significance