Part 1. 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.
Part 2. Example
Steps: (1) Solar radiation reaches Earth's atmosphere (2) Some is reflected back into space (3) The rest of the energy is absorbed by land and oceans, heating the Earth (4) Some of this heat is trapped by greenhouse gases in the atmosphere (5) Human activities such as burning fuel are increasing the amount of greenhouses gases (6) This causes more heat radiation to stay trapped in our atmosphere (7) The Earth's temperature rises  
Where does the following step fit into the given list of steps: Heat radiates from Earth to space 
Answer:  After step 3. 
Explanation: The correct answer is 'After step 3'. The given step is 'Heat radiates from Earth to Space'. Step 3 introduces a new concept of generated heat. Step 4 mentions that the heat is trapped into the atmosphere. In order for the heat to get to the atmosphere, the heat must radiate from Earth to space. Therefore, the correct answer is 'After step 3.'
Part 3. Exercise
Steps: (1) Sunlight passes through the glass into the greenhouse (2) The absorbed sunlight is converted to heat (3) The heat cannot escape the glass (4) The heat is trapped in the greenhouse (5) The hot air rises (6) The colder air at the top is pushed to the bottom (7) The colder air is then warmed by the floor and the plants.  
Where does the following step fit into the given list of steps: The plants and floor absorb the the sunlight 
Answer:
 After step 1. 