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'.
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Question: Problem: 42 persons can repair a road in 12 days , working 5 hours a day . in how many days will 30 persons , working 6 hours a day , complete the work ?
Options: a ) 10 , b ) 16 , c ) 13 , d ) 14 , e ) 19

Answer: d

Question: Problem: 82 a 7 + 6 b ____ 190 if a and b represent positive single digits in the correctly worked computation above , what is the value of a + 2 b ?
Options: a ) 2 , b ) 6 , c ) 9 , d ) 11 , e ) 12

Answer: b

Question: Problem: tabby is training for a triathlon . she swims at a speed of 1 mile per hour . she runs at a speed of 9 miles per hour . she wants to figure out her average speed for these two events . what is the correct answer for her ?
Options: a ) 8 mph , b ) 5.25 mph , c ) 3.5 mph , d ) 5 mph , e ) 0.5 mph

Answer:
d