Marcelina has over

songs on her mobile phone, and she wants to estimate the average length of the songs (in minutes). She takes an of

songs on her phone and calculates a sample mean of

minutes and a standard deviation of

minutes. The song lengths in the sample were roughly symmetric with no clear outliers.
Based on this sample, which of the following is a

confidence interval for the mean length (in minutes) of the songs on her phone?