33. Box plots have been used successfully to describe
a. center and spread of a data set
b. the extent and nature of any departure from symmetry
c. identification of "outliers"
d. All of the choices.
e. none of the choices

34. A civil engineer is analyzing the compressive strength of concrete. Compressive strength is normally distributed with variance 1000(psi)². A random sample of 10 specimens has a mean compressive strength of 3250 psi. With what degree of confidence could we say that the mean compressive strength between 3235 and 3265?
a. 90%
b. 87%
c. 95%
d. 85%
e. 99%