Answer:

Explanation:
Maximum height of the pumpkin, 
Initial speed, v = 22 m/s
We need to find the angle with which the pumpkin is fired. the maximum height of the projectile is given by :

On rearranging the above equation, to find the angle as :



So, the angle with which the pumpkin is fired is 39.49 degrees. Hence, this is the required solution.
In a real system of levers, wheels, or pulleys, the AMA is less than the IMA because of friction.
AMA (Actual mechanical advantage) is found by dividing output force by effort force. The actual mechanical advantage will always be less than the ideal mechanical advantage. The ideal mechanical advantage assumes perfect efficiency which doesn't account for friction, while actual mechanical advantage does. Therefore; the IMA is always greater than the actual mechanical advantage because all machines must overcome friction.
We don't know the change in velocity, so can't answer.
In an extremely simplified explanation,
What happens is that the steam (heat) that is generated by the burning of coal is used to rotate the motor of the steam engine.