Definition: 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.
Input: Steps: (1) Waves hit the coast (2) Waves have energy that pushes the water and sediment (3) The sediment can help erode land like sandpaper (4) Water washes the sediment back  
Where does the following step fit into the given list of steps: Some sediment is left as sand. 
Output:
 After step 4. 