The primary aim of a study by Carter et al. was to investigate the effect of the age at onset of bipolar disorder on the course of the illness. One of the variables investigated was family history of...

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Extracted text: The primary aim of a study by Carter et al. was to investigate the effect of the age at onset of bipolar disorder on the course of the illness. One of the variables investigated was family history of mood disorders. Table 2 shows the frequency of a family history of mood disorders in the two groups of interest (Early age at onset defined to be 18 years or younger and Later age at onset defined to be later than 18 years.). Table 2: Frequeney of Family History of Mood Disorder by Age Group Among Bipolar Subjects Family History of Mood Disorders Early = 18(E) Later > 18(L) Total Negative (A) AC AA AC+AA Unipolar (B) DA CC DA+CC Bipolar (C) AB СВ AB+CB Unipolar & Bipolar (D) Total BC AD BC+AD AC+DA+AB+BC AA+CC+CB+AD Where A, B, Cand D are 1", 2d, 3d and 4 digits of your SAP IDs. i.e. if SAP ID=12345, then A=1, B=2, C=3 and D=4. Page 2 of 3 (a) What is the probability that a person picked at random from the subjects will be Early (E) and will be a person who has no family history of mood disorders (A)?