a person exerts a force of 200 Newton in order to pull a mass of 100 kg of to the height of 2 m using a ladder with efficiency 80% what is the minimum height of the ladder​

1. explain how you calculate the net force in any direction on the box. 2. suppose an upward force of 15n is added to the box. what will be the net vertical force on the box? 3. what force could be applied to the box to make the net force in the horizontal direction zero? explain. 4. suppose a force of 25n to the right is added to the box. what will be the net force to the right?