A 1000-Kg Helicopter Hovers Over a Forest Fire and Starts

Multiple Choice

A 1000-kg helicopter hovers over a forest fire and starts to squirt water downward with a speed of 10 m/s at a rate of 40 kg/s. What is the initial upward acceleration on the helicopter when it first starts to release the water?

A) 2.5 m/s²
B) 0.40 m/s²
C) 0.25 m/s²
D) 4.0 m/s²
E) 5.0 m/s²