19. If you are watching a moving train, what would happen to the pitch of the whistle at a crossing as the locomotive approaches and then passes by the crossing?
a. The pitch would remain the same.
b. The pitch would increase suddenly as the train passed.
C. The pitch would decrease and then increase again.
d. The pitch would decrease suddenly as the train passed.

Asubject in a clinical research trial experiences a serious, unanticipated adverse drug experience. how should the investigator proceed, with respect to the irb, after the discovery of the adverse event occurrence? a. do not report the adverse drug experience to the irb since it is a common adverse experience.b. report the adverse drug experience to the irb only if there are several other occurrences.c. report the adverse drug experience as part of the continuing review report.d. report the adverse drug experience in a timely manner, in keeping with the irb's policies and procedures, using the forms or the mechanism provided by the irb.