To investigate whether or not sexism was present in the workplace,
male bank supervisors were each given a personnel file and asked to judge whether the person represented in the file should be recommended for promotion or whether the person's file should be held. The files were identical except that half of the files were labeled Male and the other half Female. The data is summarized below.
  Promote No Promotion Total
Male
Female
Total

Which of the following statements are true? Select all that apply.

is a marginal frequency

is a joint frequency

is a marginal frequency

is a joint frequency

is a joint frequency

is a joint frequency