Answer:
The right answer is (D) 340m
Step-by-step explanation:
If the package is dropped from a helicopter moving upward and the air resistance is negligible, the only acting force in the package is the gravity force. Therefore you can consider this as a Vertical Projectile Motion problem.
The initial speed of the package V₀ is 15m/s.
The acceleration of the package G is 9.8m/s².
The initial hight is Y₀. Therefore:
Y(t)=Y₀+V₀·t-0.5·G·t²
But we know than T(10s)=0m
0m=Y₀+150m-490m
Y₀=340m