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

Q: Problem: how many 3 - digit positive integers are there , where each digit is positive , and no 3 adjacent digits are same ? 
Options: a ) 1236 , b ) 504 , c ) 4096 , d ) 4608 , e ) 6561

A: b
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Q: Problem: a dog is tied to a tree by a long nylon cord . if the dog runs from the due north side of the tree to the due south side of the tree with the cord extended to its full length at all items , and the dog ran approximately 30 feet , what was the approximate length of the nylon cord e , in feet ? 
Options: a ) 30 , b ) 25 , c ) 15 , d ) 10 , e ) 5

A: d
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Q: Problem: in the biology lab of ` ` jefferson ' ' high school there are 0.036 * 10 ^ 5 germs , equally divided among 45000 * 10 ^ ( - 3 ) petri dishes . how many germs live happily in a single dish ? 
Options: a ) 10 , b ) 20 , c ) 30 , d ) 60 , e ) 80

A:
e
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