A study of the career paths of hotel general managers sentquestionnaires to an SRS of 250 hotels belonging to major U.S.hotel chains. There were 127 responses. The average time these 127general managers had spent with their current company was 8.92years. (Take it as known that the standard deviation of time withthe company for all general managers is 2.8 years.)
(a) Find the margin of error for a 90% confidence interval toestimate the mean time a general manager had spent with theircurrent company: years
(b) Find the margin of error for a 99% confidence interval toestimate the mean time a general manager had spent with theircurrent company: years
(c) In general, increasing the confidence level the margin oferror (width) of the confidence interval. (Enter: ''DECREASES'',''DOES NOT CHANGE'' or ''INCREASES'', without the quotes.)
