For each of the following, state whether the events created are mutually exclusive and whether they are collectively exhaustive.
a. Undergraduate business students were asked whether they were sophomores or juniors.
b. Each respondent was classified by the type of car he or she drives: sedan, SUV, American, European, Asian, or none.
c. People were asked, "Do you currently live in (i) an apartment or (ii) a house?"
d. A product was classified as defective or not defective.