Joe jumps from an aircraft cruising at a height of 3050 meters and traveling at 62.5 m/s along the horizon. How long does Joe have to deploy his parachute?
from your brief description it is not clear whether we take air resistance into account and if Joe has to deploy the parachute at a minimun altitude in order to survive landing.
so if we consider a trajectory in vacuum, your solution should be given by the time of flight formula: http://en.wikipedia.org/wiki/Trajectory_of_a_projectile#Time_of_flight
,which can be calculated here:
for angle of zero it is 24.9 sec to impact.
let us know if you do take air resistance and minimum deployment height into consideration.