You need to answer the question 'Are the given steps in order?', given a set of steps describing a process. Your answer must be either Yes or No. If the answer is No, that means the steps are out of order and do not make sense in the order they are in. If the answer is Yes, that means the steps are in order and make sense in the order that they are in. A set of steps are not in order if the steps reference information that is introduced in a later step

Example Input:  ['Food leaves the esophagus and enters the stomach', 'The stomach churns the food', 'With the aid of stomach acids', 'The food becomes a thick liquid', 'Is then passed to the small intestine.'] 
Example Output:   Yes  

Example Input:  ['The oil is transported to stores', 'Oil is placed into a stove in the house', 'Oil is purchased by homeowners', 'The warm air off of the oil travels through the house', 'The oil is lit on fire, and burns for a long time', 'Oil is gathered through mining operations'] 
Example Output:   No  

Example Input:  ['Iron is exposed to oxygen', 'A chemical reaction occurs', 'The iron starts to oxidize', 'The iron starts to rust.', 'Is exposed to air'] 
Example Output:
  No