Final answer:
In space and stationary, the baseball will remain stationary. When hit with a bat, the ball will move in the direction of the strike. With a jetpack firing, the ball will accelerate in the opposite direction.
Step-by-step explanation:
In the first scenario, when the baseball is in space and stationary, it will remain stationary due to the absence of external forces. Without the force of gravity acting on it, the ball will not fall or float away.
In the second scenario, when the ball is in space and someone hits it with a bat, the ball will move in the direction of the bat strike due to Newton's third law. In the absence of air resistance, the ball will continue moving in a straight line at a constant speed.
In the third scenario, when the ball has a small jetpack attached that is continuously firing, it will accelerate in the direction opposite to the jetpack thrust. The force from the jetpack will cause the ball to move in a straight line, accelerating in the opposite direction.