Let's say we analyzed data from a population of N = 120 males who had both a screening test for prostate cancer (PSA test) and a diagnostic test for prostate cancer (biopsy). Suppose we had a different test for prostate cancer what produces a numerical risk that classifies a male as low, moderate, or high risk for prostate cancer. A sample of 120 males undergo the new test and have a biopsy. Use the following dataset from this new test and biopsy below to answer Questions 1-5.

Prostate Test Risk	Prostate Cancer	No Prostate Cancer	Total
Low	15	60	75
Moderate	10	20	30
High	5	10	15
Total	30	90	120

1. What is the probability of low risk?
   1. 30/120
   2. 75/120
   3. 15/120
   4. 60/120