A boy finds that he can use a uniform plank of wood for a seesaw if he tries to balance it
2 m from the end using a tree trunk as the
pivot. If the boy sits at the end of the shorter
side, the plank will balance the boy's weight.
If the plank is 7 m long and weighs 500 N.
What is the weight of the boy? ​

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.