In a major city, 4% of the population has

In a major city, 4% of the population has
In a major city, 4% of the population has Klingon Influenza. In a certain hospital, a test for Klingon Influenza is administered. The test is 97% effective in detecting the disease in those people having the disease. People not having the disease test positive 2% of the time. What is the probability that:

A. A person testing positive with this disease actually has the disease?

B. A person testing positive with this disease, in fact, does not have the disease?

C. A person testing negative for this disease actually has the disease?

D. A person testing negative for this disease, in fact, does not have the disease?