question 5 please show work :)

5. Two cities had a population of 3,000,000. Death rate from all causes in Metro City was 50 per 100,000. Death rate from all causes in Suburban City was 80 per 100,000. Cancer deaths in both cities were 4 per 100,000 per city, risk of cancer-caused death for both cities was the same. What is the relationship in terms of proportionate cancer mortality (PCM) rates between the two cities? (5 points) a. PCM rate in Metro City > PCM rate in Suburban City b. PCM rate in Metro City - PCM rate in Suburban City C. PCM rate in Metro City