In this task, you need to provide the correct option for a given problem from the provided options.
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Question: Problem: one fast typist type some matter in 2 hrs and another slow typist type the same matter in 3 hrs . if both do combine in how much time they will take to finish . 
Options: a ) 10 , b ) 11 , c ) 12 , d ) 13 , e ) 14

Answer: c


Question: Problem: what is the square root of 6,561 ? 
Options: a ) 18 , b ) 9 , c ) 45 , d ) 62 , e ) 81

Answer: e


Question: Problem: in assembling a bluetooth device , a factory uses one of two kinds of modules . one module costs $ 15 and the other one , that is cheaper , costs $ 10 . the factory holds a $ 140 worth stock of 13 modules . how many of the modules in the stock are of the cheaper kind ? 
Options: a ) 20 , b ) 25 , c ) 30 , d ) 11 , e ) 35

Answer:
d