How High Must the Plane Fly to Drop Supplies Accurately?

[Prototype44]

Homework Statement

Need help solving this problem

An emergency relief plane is dropping a care package from a plane to a group of medical personnel working for a relief agency in an African village. The package is designed to land in a small lake, inflate an attached raft upon impact, and finally resurface with the raft side down. The plane will be moving horizontally with a ground speed of 59.1 m/s. The package will be dropped a horizontal distance of 521 m from the intended target location. At what altitude above the pond must the plane be flying in order to successfully accomplish this feat?

yf=0m yi=? Viy=? t=8.82s

Homework Equations

yf=yi+Viyt+1/2at^2

The Attempt at a Solution

Not sure where to go from here

 

[Prototype44]

Nm I solved it assuming Viy=0m/s