Need help with math questions data management

By convention, an outlier is a point that is at least O a) 1.5 standard deviations from the mean O b) 1.5 standard deviations from Q1 or Q3 O C) 1.5 standard deviations from the next greatest datum O d) 1.5 standard deviations from the medianWhich is a correct statement? O a) The median is also known as the second quartile O b) The first quartile is the median of the lower half of the data O C) The third quartile is the median of the upper half of the data d) All three statements are correct