Suppose a certain ophthalmic trait is associated with eye color. Three hundred randomly selected individuals are studied, with results given in the following table.
a. What is the probability that a person selected at random has blue eyes?
b. What is the probability that a person selected at random has the trait?
c. Are events $A$ (has blue eyes) and $B$ (has the trait) independent? Justify your answer.
d. How are the two events $A$ (has blue eyes) and $C$ (has brown eyes) related-independent, mutually exclusive, complementary, or all-inclusive? Explain why or why not each term applies.