USA Europe Total Aware 670 520 1,190 Unaware 330 480 810 Total 1,000 1,000 2,000 a. Give an example of a simple event. b. Give an example of a joint event. c. Find the complement of the set of respondents who are from Europe. d. Why is the set of respondents who are unaware and are from Europe a joint event? 4.11 Referring to the contingency table in Problem 4.10, if a re- spondent is selected at random, what is the probability that a. the respondent is from the USA? b. the respondent is unaware of the 2012 oil spill? c. the respondent is unaware of the spill or is from USA? d. Explain the difference in the results in (b) and (c)