An airplane is flying at 150 ft/s at an altitude of 2000 ft in a direction that will take it directly over an observer at ground level. Find the rate of change of the angle of elevation between the observer and the plane when the plane is directly over a point on the ground that is 2000 ft from the observer.

The frequency of a given region of the electromagnetic spectrum ranges from 3 × 1016 − 3 × 1019 hertz. which type of wave is found in this region? a. x-rays b. ultraviolet rays c. infrared waves d. radio waves

Asample of a gaseous substance changes into liquid. this process is called (blank) and it takes place when heat is (blank) a gaseous system

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.