If a drone flies 8 m/s due East with respects to the wind and the wind is blowing 6 m/s due North, the speed of the drone with respect to the ground is its displacement.
Displacement is calculated using Pythagoras theorem.
d² = 8²+6²
d² = 64+36
d² = 100
Square root both sides
√d² = √100
d = 10m/s
Hence the distance of the drone with respect to the ground is 10m/s
In order to know how long it has been falling for you take the final velocity "49m/s" and divide it by the acceleration "9.8m/s" and get 5, since you have been using seconds in the calculations the answer is 5 seconds. (Fun fact, it is actually 9.82m/s per second since it accelerates and they rounded it down.)