Answer:
The ball will fall on the X .
Explanation:
At height, when the aeroplane is in great speed , everything attached with it acquires the same speed . So ball will also have the same speed as the aeroplane have. When ball starts falling off , it gets detached from plane but , at the same time it continues to travel with its earlier speed , because of inertia of motion. So it remains stationary with respect to plane in horizontal direction . It has velocity with respect to plane only in vertical direction. Hence it will fall on the X. It is due to first law of motion.
I think 36m/12s because 3×12 =36
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