Drag the cannon downwards so it is at ground level, or 0 m (which represents the initial height of the object), then fire the pumpkin straight upward (at an angle of 90∘) with an initial speed of 14 m/s. how long does it take for the pumpkin to hit the ground?

2.854 seconds

Explanation:

t = Time taken

u = Initial velocity

v = Final velocity

s = Displacement

a = Acceleration due to gravity = 9.81 m/s²

Time taken by the pumpkin to go up is 1.427 seconds

The pumpkin will take the same time to reach the ground.

So, time taken by the ball to reach the ground is 1.427+1.427 = 2.854 seconds