A Sample of 75 Information Systems Managers Had an Average

Multiple Choice

A sample of 75 information systems managers had an average hourly income of $40.75 with a standard deviation of $7.00.The 95% confidence interval for the average hourly wage (in $) of all information system managers is

A) 38.61 to 42.89.
B) 39.40 to 42.10.
C) 39.14 to 42.36.
D) 37.54 to 43.96.