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: annika hikes at a constant rate of 12 minutes per kilometer . she has hiked 2.75 kilometers east from the start of a hiking trail when she realizes that she has to be back at the start of the trail in 40 minutes . if annika continues east , then turns around and retraces her path to reach the start of the trail in exactly 40 minutes , for how many kilometers total did she hike east ? 
Options: a ) 3.625 , b ) 3.5 , c ) 3 , d ) 3.04 , e ) 4

Answer: d


Question: Problem: annie and sam set out together on bicycles traveling at 15 and 12 km per hour respectively . after 40 minutes , annie stops to fix a flat tire . if it takes annie 30 minutes to fix the flat tire and sam continues to ride during this time , how many minutes will it take annie to catch up with sam assuming that annie resumes riding at 15 km per hour ? 
Options: a ) 20 , b ) 40 , c ) 60 , d ) 80 , e ) 100

Answer: d


Question: Problem: earl can stuff advertising circulars into envelopes at the rate of 36 envelopes per minutes and ellen requires a minutes and half to stuff the same number of envelops . working together , how long will it take earl and ellen to stuff 120 envelopes 
Options: a ) 2 minutes , b ) 5 minutes , c ) 7 minutes , d ) 3 minutes , e ) 4 minutes

Answer:
a