Bags of a certain brand of tortilla chips claim to have a net weight of 14 ounces. A representative of a consumer advocate group wishes to see if there is any evidence that the mean net weight is less than advertised and plans to construct a 95% confidence interval for the mean, using an SRS of 16 bags. Suppose he is not sure if the distribution of net weights is Normal. In which of the following circumstances would he not be safe to use a t procedure?
A. A boxplot of the data has multiple large outliers.
B. The mean and median of the data are nearly equal.
C. The sample standard deviation is large.
D. A boxplot of the data shows a very slight skew.

A) The normal distribution does not have outliers. The outliers are any point outside the 3σ interval which 99.7% of the data. The 0.3% data would not be outliers.

B) YEs the mean and median of the normal distribution are nearly equal. AS it is asymmetrical.

C) When the sample standard deviation is large the data is spread about the mean. The normal distribution is flatter and wider

D) The normal distribution is never skewed.If one end is longer then the distribution is not assymmetric and the normal distribution asymmetric meaning half is the mirror reflection of the other half.

So A and D indicate circumstances where he not be safe to use a t procedure.