Question 1 and 2 are based on the following information:

The incidence of heart attacks among smokers in a community is 30.0 per 100,000 per year. The incidence of heart attacks among non-smokers in this community is 4.0 per 100,000 per year. The proportion of non-smokers in this community is 75%.

1) What proportion of the risk of heart attacks among smokers can be attributed to smoking? (Select one)

a. 6.5%

b. 26.0%

c. 76.0%

d. 86.7%

2) What proportion of the risk of heart attacks in the total populationcan be attributed to smoking? (Select one)

a. 21.3%

b. 61.9%

c. 82.2%

d. Cannot be calculated given the information provided.