In metropolitan areas, a considerable number of employees commute to their workplaces

using their own cars. A research project was conducted to determine the commute time of

employees in Ankara using their cars. The study involved collecting commute time data in

minutes from a sample of $30$ individuals in the Ankara region.

a$)$ Determine a $90\%$ confidence interval for the mean commuting time of all commuters

in Ankara. Interpret the results.

b$)$ At the $0\mathrm{.}05$ significance level, is it reasonable to conclude the mean commuting time

of all commuters is now $35?$ Interpret the results.

c$)$ At the $0\mathrm{.}01$ significance level, is it reasonable to conclude the mean commuting time

of all commuters is now less than $20?$ Interpret the results.