Answer:
The bomb will remain in air for 17.5 s before hitting the ground.
Step-by-step explanation:
Given:
Initial vertical height is,

Initial horizontal velocity is,

Initial vertical velocity is,

Let the time taken by the bomb to reach the ground be 't'.
So, consider the equation of motion of the bomb in the vertical direction.
The displacement of the bomb vertically is

Acceleration in the vertical direction is due to gravity,

Therefore, the displacement of the bomb is given as:

So, the bomb will remain in air for 17.5 s before hitting the ground.