This is
{HH, TT, TH, HT} where H = head and T = tail
Answer:
Sample relative risk is 4.
Step-by-step explanation:
We are given the following in the question:
Group 1 of smokers: 10 out of 100 get lung cancer.

Group 2 of non-smokers: 5 out of 200 get lung cancer

Sample relative risk:
- It is the ratio of probability of an outcome in an exposed group to the probability of an outcome in an unexposed group.
Sample relative risk =

Thus, sample relative risk is 4.