Given a list of steps and an additional step, determine where the step fits into the original list of steps. A correct answer, correctly places the given step into the set of steps so that it creates a new plausible set of steps. Output must be formatted as 'After step n', where n is the step number after which the given additional step is to be inserted.

Steps: (1) The human body takes a breath inward (2) Air is transported to the lungs (3) Air reaches the alveoli, the smallest air sacs in the lungs (4) In the alveoli, air passes into the blood within small capillaries (5) The dissolved oxygen is picked-up by red blood cells (6) The red blood cells bind the oxygen via a protein called heme (7) Red blood cells circulate throughout the body and reach the various tissues (8) Within small capillaries, the heme release the oxygen (9) The oxygen can then reach the cells within the tissue  
Where does the following step fit into the given list of steps: The gaseous oxygen in the air dissolves into the capillary blood 
 After step 4. 

Steps: (1) Grass and small plants grow in an area (2) These plants die (3) The soil becomes more fertile (4) Larger plants are able to be supported (5) Trees eventually grow.  
Where does the following step fit into the given list of steps: The soil gains organic material 
 After step 2. 

Steps: (1) Coal is loaded into the firebox (2) The boiler produces steam under high pressure (3) The steam generated in the boiler flows down into a cylinder (4) Just ahead of the wheels, pushing a tight-fitting plunger, the piston (5) As the piston pushes, the crank and connecting rod turn the locomotive&#x27;s wheels and power the train along (6) An outlet valve opens and the piston pushes the steam back through the cylinder and out up the locomotive&#x27;s chimney  
Where does the following step fit into the given list of steps: The piston is connected to one or more of the locomotive&#x27;s wheels through a kind of arm-elbow-shoulder joint called a crank and connecting rod 

 After step 4.