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: a river boat leaves silver town and travels upstream to gold town at an average speed of 6 kilometers per hour . it returns by the same route at an average speed of 5 kilometers per hour . what is the average speed for the round - trip in kilometers per hour ? 
Options: a ) 5.5 , b ) 7.1 , c ) 7.2 , d ) 7.0 , e ) 8.0

Answer: a


Question: Problem: an intern wants to label folders with numbers using digit stickers only . if the intern uses 999 stickers , how many folders have been numbered ? ( the numbers of the folders are consecutive and the number of the first folder is 1 ) . 
Options: a ) 287 , b ) 369 , c ) 370 , d ) 371 , e ) 430

Answer: b


Question: Problem: a car covers a distance of 624 km in 2 2 / 5 hours . find its speed ? 
Options: a ) 104 kmph , b ) 194 kmph , c ) 109 kmph , d ) 260 kmph , e ) 271 kmph

Answer:
d