In this task, you need to answer the given multiple-choice question on the physics. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

Q: Problem: a cube of side two meter length is cut into small cubes of side 10 cm each . how many such small cubes can be obtained ? 
Options: a ) 2878 , b ) 2778 , c ) 1000 , d ) 8000 , e ) 8900

A: d
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Q: Problem: a hollow iron pipe is 21 cm long and its external diameter is 8 cm . if the thickness of the pipe is 1 cm and iron weights 8 g / cm cube , then find the weight of the pipe . 
Options: ['a ) 3.696 kg', 'b ) 3.686 kg', 'c ) 2.696 kg', 'd ) 2.686 kg', 'e ) none of these']

A: a
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Q: Problem: a train running at the speed of 180 km / hr crosses a pole in 8 seconds . find the length of the train . 
Options: a ) 150 , b ) 88 , c ) 480 , d ) 288 , e ) 400

A:
e
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