This task is about creating an unanswerable question based on a given passage. Construct a question that looks relevant to the given context but is unanswerable. Following are a few suggestions about how to create unanswerable questions:
(i) create questions which require satisfying a constraint that is not mentioned in the passage
(ii) create questions which require information beyond what is provided in the passage in order to answer
(iii) replace an existing entity, number, date mentioned in the passage with other entity, number, date and use it in the question
(iv) create a question which is answerable from the passage and then replace one or two words by their antonyms or insert/remove negation words to make it unanswerable.

Q: Passage: Even though some proofs of complexity-theoretic theorems regularly assume some concrete choice of input encoding, one tries to keep the discussion abstract enough to be independent of the choice of encoding. This can be achieved by ensuring that different representations can be transformed into each other efficiently.

A: What can not be achieved by ensuring different representations can transformed into each other efficiently?
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Q: Passage: Due to its location, the Punjab region came under constant attacks and influence from the west and witnessed centuries of foreign invasions by the Greeks, Kushans, Scythians, Turks, and Afghans. The city of Taxila, founded by son of Taksh the son Bharat who was the brother of Ram. It was reputed to house the oldest university in the world,[citation needed] Takshashila University. One of the teachers was the great Vedic thinker and politician Chanakya. Taxila was a great centre of learning and intellectual discussion during the Maurya Empire. It is a UN World Heritage site, valued for its archaeological and religious history.

A: Who has Punjab invaded?
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Q: Passage: There is an extensive network of caves, including Wookey Hole, underground rivers, and gorges, including the Cheddar Gorge and Ebbor Gorge. The county has many rivers, including the Axe, Brue, Cary, Parrett, Sheppey, Tone and Yeo. These both feed and drain the flat levels and moors of mid and west Somerset. In the north of the county the River Chew flows into the Bristol Avon. The Parrett is tidal almost to Langport, where there is evidence of two Roman wharfs. At the same site during the reign of King Charles I, river tolls were levied on boats to pay for the maintenance of the bridge.

A:
Where does the Axe river flow into?
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