A study by Peter D. Hart Research Associates for the Nasdaq Stock Market revealed that $43 \%$ of all American adults are stockholders. In addition, the study determined that $75 \%$ of all American adult stockholders have some college education. Suppose $37 \%$ of all American adults have some college education. An American adult is randomly selected.
a. What is the probability that the adult owns stock and has some college education?
b. What is the probability that the adult owns no stock and has some college education?
c. What is the probability that the adult owns stock and has no college education?
d. What is the probability that the adult neither owns stock nor has some college education?