TASK DEFINITION: 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'.
PROBLEM: 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

SOLUTION: d

PROBLEM: Problem: a 600 meter long train crosses a signal post in 15 seconds . how long will it take to cross a 3 kilometer long bridge , at the same speed ? 
Options: a ) 4 min , b ) 2 min , c ) 8 min , d ) 9 min , e ) 1.5 min

SOLUTION: e

PROBLEM: Problem: a man swims downstream 100 km and upstream 30 km taking 10 hours each time ; what is the speed of the current ? 
Options: a ) 2.5 , b ) 3.5 , c ) 4.5 , d ) 5.3 , e ) 3.4

SOLUTION:
b