Unoccupied Seats on Flights Cause Airlines to Lose Revenue $\left[ \begin{array} { l l } 11.06 & 12.14\end{array} \right]$

Unoccupied seats on flights cause airlines to lose revenue.Suppose a large airline wants to estimate its average number of unoccupied seats per flight over the past year.225 flight records are randomly selected and the number of unoccupied seats is noted,with a sample mean of 11.6 seats and a standard deviation of 4.1 seats.Calculate a 95 percent confidence interval for ?,the mean number of unoccupied seats per flight during the past year.

A) $\left[ \begin{array} { l l } 11.06 & 12.14\end{array} \right]$
B) $[ 11.34 = 11.86 ]$
C) $\left[ \begin{array} { l l } 10.44 & 12.76\end{array} \right]$
D) $\left[ \begin{array} { l l } 11.15 & 12.05\end{array} \right]$
E) $\left[ \begin{array} { l l } 3.56 & 19.64\end{array} \right]$